阅读说明：本技术 波束域网络大规模mimo无线光通信系统及通信方法 (The extensive MIMO radio optical communication system of Beam Domain network and communication means ) 是由 孙晨 高西奇 王家恒 赵佳 于 2019-08-14 设计创作，主要内容包括：本发明提供了一种波束域网络大规模MIMO无线光通信系统及通信方法,该系统包括至少两个光发送节点和至少两个光接收节点,每个光发送节点包括一个光发送单元阵列与一个发送透镜,每个光接收节点包括一个光接收单元阵列与一个接收透镜。该方法为：单个光发送单元发出的光经过发送透镜形成一个窄波束,利用光发送单元阵列与发送透镜,生成多个不同方向的发送窄波束；不同方向的发送窄波束经过接收透镜折射到不同的光接收单元进行接收检测；每个光发送节点利用不同的波束同时向不同的光接收节点发送信号,每个光接收节点利用不同的接收波束同时接收多个不同位置的光发送节点的发送信号。本发明能显著提升传输数据流数,并克服因遮挡而通信中断的问题。(The present invention provides a kind of extensive MIMO radio optical communication system of Beam Domain network and communication means, the system includes at least two smooth sending nodes and at least two light-receiving nodes, each smooth sending node includes a light transmission unit array and a transmission lens, and each light-receiving node includes a light receiving unit array and a receiving lens.This method are as follows: the light that single light transmission unit issues using light transmission unit array and sends lens, generate the transmission narrow beam in multiple and different directions by sending one narrow beam of lens forming；The transmission narrow beam of different directions is refracted to different light receiving units by receiving lens and carries out reception detection；Each smooth sending node sends signal to different light-receiving nodes simultaneously using different wave beams, and each light-receiving node receives the transmission signal of the light sending node of multiple and different positions using different reception wave beams simultaneously.The present invention can be obviously improved transmitting data stream number, and overcome the problems, such as because blocking due to communication disruption.)

1. a kind of extensive MIMO radio optical communication system of Beam Domain network, which is characterized in that send and save including at least two light Point and at least two light-receiving nodes, each light sending node send saturating including a light transmission unit array and one Mirror, each smooth transmission unit array are made of one group of light transmission unit, and each light-receiving node includes a light-receiving Cell array and a receiving lens, each light receiving unit array are made of one group of light receiving unit.

2. the extensive MIMO radio optical communication system of Beam Domain network according to claim 1, which is characterized in that the light Transmission unit array is located on the focal plane for sending lens；The light receiving unit array is located at the receiving lens On focal plane.

3. the extensive MIMO radio optical communication system of Beam Domain network according to claim 1, which is characterized in that at least two A light sending node is distributed in different location, collectively covers same communication zone, each in the smooth transmission unit array The light that light transmission unit issues reflects to form a light beam by lens, and the light beam that adjacent smooth transmission unit generates is in light intensity The place for decaying to half is overlapping, and the light beam for being separated by one or more light transmission unit generation does not overlap；At least two Light-receiving Node distribution is refracted to corresponding light receiving unit by receiving lens in different location, incident ray, and single light connects The reception wave beam in the corresponding direction of unit is received, there are overlapping regions for the corresponding reception wave beam of adjacent light receiving unit, are separated by 1 The corresponding reception wave beam of a or multiple light receiving unit does not overlap.

4. a kind of method for carrying out MIMO wireless light communication with the extensive MIMO radio optical communication system of above-mentioned Beam Domain network, It is characterized in that, this method are as follows:

The light that single light transmission unit issues using light transmission unit array and is sent by sending one narrow beam of lens forming Lens generate the transmission narrow beam in multiple and different directions；The transmission narrow beam of different directions is refracted to difference by receiving lens Light receiving unit carry out reception detection；Each smooth sending node is sent out to different light-receiving nodes simultaneously using different wave beams The number of delivering letters, each light-receiving node receive the transmission of the light sending node of multiple and different positions using different reception wave beams simultaneously Signal.

5. MIMO wireless light communication method according to claim 4, which is characterized in that the smooth sending node sends signal In the process, its known channel information for arriving different light-receiving nodes of each smooth sending node, the channel information are that light sends section One or more light transmission units are put into the complete channel matrix or light sending node of light-receiving node to light-receiving node In one or more light receiving units channel submatrix.

6. MIMO wireless light communication method according to claim 5, which is characterized in that the channel information passes through uplink Road feedback obtains or estimates to obtain by uplink, and when channel information is obtained by uplink feedback, light sends section Point passes through other uplink feedbacks to light-receiving node pilot signal transmitted, light-receiving node estimating channel information, so that Light sending node obtains channel information；When channel information is estimated to obtain by uplink, light sending node configures additional Light receiving unit, light-receiving node configure additional light transmission unit, and light-receiving node is led by additional uplink transmission Frequency signal, light sending node estimates corresponding channel information, and obtains light sending node according to light reversibility pricinple and connect to light Receive the channel information of node.

7. MIMO wireless light communication method according to claim 4, which is characterized in that the smooth sending node sends signal In the process, at least two light sending node, which is combined to light-receiving node, sends signal or each smooth sending node independently to light Receiving node sends signal；Described at least two light sending node is combined to the method that light-receiving node sends signal, will The channel coefficients of multiple smooth sending nodes to light-receiving node constitute channel matrix, are sent using the channel matrix co-design pre- Coding；The independent method for sending signal to light-receiving node of each smooth sending node is that each smooth sending node is according to it To the channel matrix of light-receiving node, independent design sends precoding, sends individual data signal.

8. MIMO wireless light communication method according to claim 4, which is characterized in that the transmission of the smooth sending node is believed Number use maximum ratio transmission or regularization force zero precoding sending method, light sending node according to channel information design based on maximum Than transmitting or regularization force zero pre-coding matrix, signal is sent to light-receiving node using pre-coding matrix；Alternatively, the light hair The transmission signal of node is sent to divide multiple access transmission method using wave beam, light sending node is different light-receiving sections according to channel information The light transmission unit set that point distribution does not overlap, the letter of different light-receiving nodes is sent using different light transmission unit set Number.

9. MIMO wireless light communication method according to claim 4, which is characterized in that the light-receiving node receives signal In the process, each light-receiving node estimates each smooth sending node to its channel information, which is institute in light sending node Have in the complete channel matrix or light sending node of all light receiving units of the light transmission unit to light-receiving node 1 or The channel submatrix of multiple smooth transmission unit one or more light receiving units into light-receiving node.

10. MIMO wireless light communication method according to claim 4, which is characterized in that described to state the reception of light-receiving node In signal process, light-receiving node uses maximum-ratio combing or least mean-square error method of reseptance according to channel information；It is described most Big ratio merges or least mean-square error method of reseptance, and multiple smooth sending nodes to its channel coefficients are constituted channel by light-receiving node Matrix designs receiving matrix according to maximum-ratio combing or minimum mean square error criterion, using receiving matrix to multiple light-receiving lists The reception signal of member carries out joint-detection；Alternatively, light-receiving node uses wave beam division multiple access method of reseptance according to channel information；Institute Wave beam division multiple access method of reseptance is stated, light-receiving node is that different light sending nodes distributes the light not overlapped according to channel information Receiving unit set, different light receiving unit set receive the transmission signal for sending node of not sharing the same light.

Technical field

The present invention relates to a kind of extensive MIMO radio optical communication system of Beam Domain network and communication means, belong to mobile logical Believe technical field.

Background technique

With the development of mobile communication, the demand of wireless transmission rate is exponentially increased, however radio spectrum resource is serious Shortage.Wireless light communication can provide additional bandwidth resources to realize high speed data transfer, be a kind of novel wireless communication Mode.Compared to Radio-Frequency Wireless Communication, wireless light communication can bring following benefit: (1) wireless light communication has very rich Frequency spectrum resource；(2) wireless light communication can not penetrate wall, thus indoor spatial multiplex gains are high, and have higher peace Quan Xing；(3) information is transmitted using light signal strength, reduces the complexity of receiving and transmitting signal processing；(4) it wireless light communication device and sets Standby market-ripe, it is cheap.

While wireless light communication brings pole wideband spectrum resource, it is also faced with huge challenge.Wireless light communication is usually adopted With amplitude modulation and intensity detection, and most of scenes only consider line of sight transmit situation, thus, the channel system of wireless light communication Number has high correlation.In the case that light sending node and light-receiving node do not configure lens, single light sending node Omnidirectional signal is sent, single transmission antenna is typically considered to, single-pass data signal can only be transmitted, single light-receiving node receives omnidirectional Signal is typically considered to single receiving antenna, can only receive single-pass data signal.Thus, the data fluxion of transmission is sent by light The limitation of node and light-receiving node number, system and rate capability are limited, thereby increases and it is possible to there is asking for due to blocking communication disruption Topic.

Summary of the invention

Goal of the invention: to solve the above-mentioned problems, the present invention proposes that a kind of extensive MIMO wireless optical of Beam Domain network is logical Letter system and communication means, light sending node is using light transmission unit array and sends lens simultaneously to multiple light-receiving nodes biography Transmission of data signal, light-receiving node receive the transmission of multiple smooth sending nodes using light receiving unit array and receiving lens simultaneously Signal is obviously improved transmitting data stream number, system velocity capacity and single node transmission rate is substantially improved, and overcome wireless optical It communicates that may be present due to blocking the problem of communication disruption.

Technical solution: to achieve the purpose of the present invention, the technical scheme adopted by the invention is that:

A kind of extensive MIMO radio optical communication system of Beam Domain network, including at least two smooth sending nodes and at least two A light-receiving node, each light sending node include a light transmission unit array and a transmission lens, Mei Geguang Transmission unit array is made of one group of light transmission unit, the light-receiving node include a light receiving unit array with One receiving lens, each light receiving unit array are made of one group of light receiving unit.

The extensive MIMO radio optical communication system of the Beam Domain network, the smooth transmission unit array are located at the hair It send on the focal plane of lens；The light receiving unit array is located on the focal plane of the receiving lens.

The extensive MIMO radio optical communication system of the Beam Domain network, at least two light sending node are distributed in not Same position, collectively covers same communication zone, and the light that each smooth transmission unit issues in the smooth transmission unit array passes through Lens reflect to form a light beam, and the light beam that adjacent smooth transmission unit generates is overlapping in the place of light intensity attenuation to half, The light beam for being separated by one or more light transmission unit generation does not overlap；At least two light-receiving Node distribution is in difference Position, incident ray are refracted to corresponding light receiving unit by receiving lens, the corresponding direction of single light receiving unit Wave beam is received, the corresponding reception wave beam of adjacent light receiving unit is separated by one or more light receiving unit there are overlapping region Corresponding reception wave beam does not overlap.

The method for carrying out MIMO wireless light communication with the extensive MIMO radio optical communication system of above-mentioned Beam Domain network, the party Method are as follows:

The light that single light transmission unit issues by sending one narrow beam of lens forming, using light transmission unit array with Lens are sent, the transmission narrow beam in multiple and different directions is generated；The transmission narrow beam of different directions is refracted to by receiving lens Different light receiving units carries out reception detection；Each smooth sending node is using different wave beams simultaneously to different light-receiving sections Point sends signal, and each light-receiving node receives the light sending node of multiple and different positions using different reception wave beams simultaneously Send signal.

The MIMO wireless light communication method, the smooth sending node are sent in signal process, each smooth sending node Its known channel information for arriving different light-receiving nodes, the channel information is complete letter of the light sending node to light-receiving node One or more light transmission units one or more light receiving units into light-receiving node in road matrix or light sending node Channel submatrix.

The MIMO wireless light communication method, the channel information obtain by uplink feedback or pass through uplink Link estimation obtains, and when channel information is obtained by uplink feedback, light sending node sends pilot tone to light-receiving node Signal, light-receiving node estimating channel information, and by other uplink feedbacks, so that light sending node obtains channel letter Breath；When channel information is estimated to obtain by uplink, light sending node configures additional light receiving unit, light-receiving node Additional light transmission unit is configured, light-receiving node passes through additional uplink pilot signal transmitted, the estimation of light sending node Corresponding channel information, and according to the channel information of light reversibility pricinple acquisition light sending node to light-receiving node.

The MIMO wireless light communication method, the smooth sending node are sent in signal process, at least two light hair It send node to combine to light-receiving node and sends signal or each smooth sending node independently to light-receiving node transmission signal；It is described At least two light sending node is combined to the method that light-receiving node sends signal, by multiple smooth sending nodes to light-receiving The channel coefficients of node constitute channel matrix, send precoding using the channel matrix co-design；Each light sends section The independent method for sending signal to light-receiving node of point is that each smooth sending node arrives the channel square of light-receiving node according to it Battle array, independent design send precoding, send individual data signal.

The transmission signal of the MIMO wireless light communication method, the smooth sending node uses maximum ratio transmission or canonical Change force zero precoding sending method, light sending node is prelisted according to channel information design based on maximum ratio transmission or regularization force zero Code matrix sends signal to light-receiving node using pre-coding matrix；Alternatively, the transmission signal of the smooth sending node uses wave Beam division multiple access sending method, light sending node are that the light that different light-receiving node distribution does not overlap is sent according to channel information Unit set sends the signal of different light-receiving nodes using different light transmission unit set.

The MIMO wireless light communication method, the light-receiving node receive in signal process, each light-receiving node Estimate each smooth sending node to its channel information, the channel information be in light sending node all smooth transmission units to light-receiving section One or more light transmission units are to light-receiving in the complete channel matrix or light sending node of all light receiving units of point The channel submatrix of one or more light receiving units in node.

The MIMO wireless light communication method, the light-receiving node of stating receive in signal process, light-receiving node root Maximum-ratio combing or least mean-square error method of reseptance are used according to channel information；The maximum-ratio combing or least mean-square error connect Receiving method, multiple smooth sending nodes to its channel coefficients are constituted channel matrix by light-receiving node, according to maximum-ratio combing or most Small mean-square error criteria designs receiving matrix, carries out joint inspection using reception signal of the receiving matrix to multiple light receiving units It surveys；Alternatively, light-receiving node uses wave beam division multiple access method of reseptance according to channel information；The wave beam division multiple access method of reseptance, Light-receiving node is that different light sending nodes distributes the light receiving unit set not overlapped, different light according to channel information Receiving unit set receives the transmission signal for sending node of not sharing the same light.

The utility model has the advantages that by adopting the above technical scheme bring the utility model has the advantages that

1. in the present invention, single light sending node can be sent more simultaneously using light transmission unit array and transmission lens The signal of a light-receiving node reduces the signal interference between different light-receiving nodes.

2. single light-receiving node receives multiple smooth sending nodes using light receiving unit array and receiving lens simultaneously Transmission signal, reduce the signal interference that do not share the same light between sending node.

3. a light sending node services multiple light-receiving nodes more than, can solve single light sending node and single light-receiving Due to the communication disruption caused by factors such as blocking between node, and multiple smooth sending nodes are simultaneously to single light-receiving node-node transmission Multichannel data information promotes the transmission rate of single node.

4. utilizing the send wave for sending lens generation different directions when light transmission unit number is more in light sending node Beam, in sending signal process, light sending node only needs to obtain the channel information that different light-receiving nodes correspond to wave beam, and in phase Signal is sent on the wave beam answered, and reduces channel information acquisition difficulty and sends the complexity of Design of Signal.

5. generating the received wave of different directions using receiving lens when light receiving unit number is more in light-receiving node Beam, receive signal process in, light-receiving node only need estimation do not share the same light sending node to its correspondence light receiving unit channel Information, and signal is received receiving detection on wave beam accordingly, it reduces channel estimation difficulty and receives the complexity of signal processing Degree.

6. there are multiple communication paths between multiple smooth sending nodes and each light-receiving node, wireless optical can be overcome It communicates that may be present due to blocking the problem of communication disruption.

Detailed description of the invention

Fig. 1 is multinode Beam Domain network wireless optical communication system schematic diagram；

Fig. 2 transmits schematic diagram for single light transmission unit to single light receiving unit；

Fig. 3 is that the transmission wave beam of single light transmission unit generates schematic diagram；

Fig. 4 is that the reception wave beam of single light receiving unit generates schematic diagram.

Specific embodiment

In order to enable those skilled in the art to better understand the solution of the present invention, below in conjunction in the embodiment of the present invention Attached drawing, the technical scheme in the embodiment of the invention is clearly and completely described, it is clear that described embodiment is only this Invention a part of the embodiment, instead of all the embodiments.Based on the embodiments of the present invention, those of ordinary skill in the art exist Every other embodiment obtained under the premise of creative work is not made, should fall within the scope of the present invention.

The invention discloses the extensive MIMO wireless light communication methods of Beam Domain network using transmitting-receiving lens.Consider L The case where light sending node is communicated with K light-receiving node, as shown in Figure 1, L light sending node is mounted on different location, often A light sending node configures M light transmission unit and sends lens, and K light-receiving node is randomly dispersed in L light sending node Coverage area in, each light-receiving node configures N number of light receiving unit and receiving lens.

Light transmission/receiving node generates different directions using light transmission/reception unit array and transmission/receiving lens Wave beam.Light transmission unit can be light emitting diode (LED) or laser diode (LD) or other sending devices；Light-receiving list Member can be photodiode or other optical detection devices.Light transmission/reception unit array uses square array or circular array Etc. one of a variety of array structures.Transmission/receiving lens can use simple lens or poly-lens structure.It is single under simple lens structure A lens cover all light transmission/reception unit, and different light transmission/reception unit generates different directions using simple lens Transmission/reception wave beam；Under poly-lens structure, single lens cover single or multiple smooth transmission/reception unit, single or multiple Light transmission/reception unit using corresponding lens generate single or multiple light send/receive wave beam.The present embodiment with light send/ For receiving node configures simple lens structure, this method can also be extended to the case where light transmission/receiving node configures poly-lens.

Light sending node generates multiple wave beams of different directions, Xiang Butong using light transmission unit array and transmission lens Light-receiving node send signal；Light-receiving node generates connecing for different directions using light receiving unit array and receiving lens Wave beam is received, the incident ray of different directions is refracted to different light receiving units by receiving lens.With single in light sending node For the light transmission of a light transmission unit single light receiving unit into light-receiving node, as shown in Fig. 2, first of light is sent The light that j-th of smooth transmission unit issues in node forms the directive transmission wave beam of tool, warp by sending lens refraction After crossing transmission, received by k-th of light-receiving node.In light-receiving node side, incident ray converges by receiving lens refraction Gather i-th of light receiving unit.

Firstly, considering that light sending node side sends the formation of wave beam.Light transmission unit by taking LED as an example, obey by the light intensity of LED Lambertian distribution, the then light that j-th of LED is issued in first of smooth sending node are with z-axis angleWhen light distribution be

Wherein,For Lambertian radiation coefficient,For the half-power launch angle of LED.Then For the light that j-th of LED is issued after sending lens refraction, the angle relative to center refracted light is ψ_l,jWhen light intensity point Cloth is

I_l,j(ψ_l,j)=T_lensI₀(r^-1ψ_l,j) (2)

Wherein, T_lensIndicate that attenuation coefficient when light is reflected by lens, r indicate that light is poly- after lens reflect Burnt degree, the distance dependent with LED and lens.Using lens are sent, the light of single led sending passes through the refraction for sending lens The wave beam with certain angle range is formed in a direction, as shown in figure 3, the direction of wave beam is determined by the horizontal position of LED, Beam angle range is determined at a distance from transmission lens by LED.Adjust LED horizontal position and its with send lens away from From so that different light transmission units generates the transmission wave beam with certain angle range in different directions, adjacent light sends single The transmission wave beam of member is overlapping in the place of light intensity attenuation to half, is separated by the transmission wave beam of one or more light transmission units generation It does not overlap.

In turn, consider from single light sending node to the transmission process of single light-receiving node.Enable ψ_k,l,jIndicate first of light In sending node in the light and first of smooth sending node of j-th of LED to k-th light-receiving node j-th of LED center light The angle of line, φ_k,lIndicate incidence angle of the incident ray in k-th of light-receiving node, d_k,lFor first of smooth sending node to kth The transmission range of a light-receiving node, A_kIndicate the receiving area of k-th of light-receiving node, then jth in first of smooth sending node The channel gain of a LED to k-th light-receiving node can be expressed as

In light-receiving node side, incident ray passes through in receiving lens refraction projection to receiving plane, i-th of light-receiving list First received signal intensity is directly proportional to the projected area of light on it, can be expressed as

h_k,i,l,j=a_k,i,l,jg_k,l,j (4)

Wherein, a_k,i,l,jThe signal strength for falling into i-th of light receiving unit is measured, is

Wherein, A_k,i,l,jIndicate light that j-th of LED of first of smooth sending node is issued the of k-th light-receiving node Projected area on i light receiving unit, A_k,l,jIndicate j-th of LED in the total projection area of k-th of light-receiving node.Projection Position it is related with the angle of incident ray, and the area A of lens_k,l,jWith the distance dependent of receiving lens and projection plane.It is single A light receiving unit can receive the light within the scope of certain angle, corresponding single reception wave beam, as shown in figure 4, receiving wave beam Corresponding direction is determined by the horizontal position of light receiving unit, receives beam angle range and receiving lens arrive light receiving unit The receiving area of distance and light receiving unit is related.Adjust the horizontal position of light receiving unit and relative to receiving lens Distance, so that different light receiving unit generates the reception wave beam of different directions, the corresponding reception wave beam of adjacent light receiving unit There are overlapping region, it is separated by the corresponding reception wave beam of one or more light receiving units and does not overlap.

Consider multiple smooth sending nodes simultaneously to the process of multiple light-receiving node-node transmission signals, each smooth sending node hair The sum of the signal of all light-receiving nodes is sent, each light-receiving node receives the transmission signal of all smooth sending nodes.It enables first Light sending node to the transmission signal of k-th of light-receiving node be x_k,l, then the reception signal of k-th of light-receiving node can be with table Up to for

Wherein, H_k,lIndicate channel matrix of first of smooth sending node to k-th of light-receiving node, (i, j) a member Element can be expressed as [H_k,l]_i,j=h_k,i,l,j, z_kTo receive noise vector, element is mutually indepedent, mean value 0, variance σ²。

Light sending node needs to obtain its channel information for arriving different light-receiving nodes before sending signal.The channel Information can be the complete channel square of all smooth transmission units all light receiving units into light-receiving node in light sending node Battle array H_k,lOr one or more light transmission units one or more light receiving units into light-receiving node in light sending node Channel submatrix.The channel information can be obtained by uplink feedback or uplink estimation.In uplink feedback side In method, light sending node passes through other uplinks to light-receiving node pilot signal transmitted, light-receiving node estimating channel information Link (optical link or radio frequency link) feeds back to light sending node.In uplink estimation method, light sending node configures volume Outer light receiving unit, light-receiving node configure additional light transmission unit, and light-receiving node is sent out by additional uplink Pilot signal is sent, light sending node estimates corresponding channel information, and obtains light sending node according to light reversibility pricinple and arrive The channel information of light-receiving node.

Light sending node according to the channel information of acquisition design send signal, can using multiple smooth sending nodes combine to Light-receiving node sends signal or multiple smooth sending nodes are independent to light-receiving node transmission signal.Using joint sending method When, the channel coefficients of L light sending node to k-th of light-receiving node are constituted into channel matrix

H_k=[H_k,1 H_k,2 … H_k,L] (7)

According to channel matrix H_kCo-design sends signal.When using independently transmitted method, each smooth sending node according to Its channel matrix H for arriving different user_k,lIndependent design sends signal, and sending node of not sharing the same light sends mutually independent data letter Number.Below by taking multiple smooth independently transmitted signals of sending node as an example, transmission Design of Signal method can be similarly applicable to multiple Light sending node joint sends the scene of signal.Light sending node designs according to channel information and sends signal x_k,l, base can be used Divide multiple access transmission method in the linear pre-coding method or use wave beam of maximum ratio transmission (MRT) or regularization force zero (RZF). The signal that light sending node is sent includes pilot signal and data-signal.Light-receiving node based on the received believe by pilot signal estimation Road information, the channel information can be all smooth transmission units all light receiving units into light-receiving node in light sending node Channel matrix H_k,lOr one or more light transmission units one or more light into light-receiving node connect in light sending node Receive the channel submatrix of unit.Light-receiving node detects the data-signal received according to channel information, can use Linearity test method or wave beam division multiple access based on maximum-ratio combing (MRC) or minimum mean square error (MMSE) receive detection Method.Specific method of sending and receiving is as follows:

(1) sending method based on MRT or RZF linear predictive coding

L light sending node sends signal to K light-receiving node simultaneously, and each smooth sending node sends K light-receiving The sum of signal of node, single light sending node send individual traffic to single light-receiving node, connect to reduce not share the same light The signal interference between node is received, the transmission signal of first of smooth sending node to k-th of light-receiving node is by independent same distribution Data symbol s_k,lBy linear predictive coding w_k,lAfter obtain, i.e.,

x_k,l=w_k,ls_k,l (8)

Wherein, precoding vector w_k,lMaximum ratio transmission (MRT) or regularization force zero (RZF) precoding two can be used Kind.Enable vector g_k,lIndicate not share the same light in first of smooth sending node transmission unit to k-th of light-receiving node channel gain, It can be expressed as

g_k,l=[g_k,l,1 g_k,l,2 … g_k,l,M]^T (9)

Wherein,When using MRT precoding, precoding vectorIt can be expressed as

Wherein,For power factor, so that sending signal x_k,lMeet corresponding power constraints, general power about Under the conditions of beam, the general power for sending signal is P_l, i.e.,Then power factorAre as follows:

For RZF precoding, precoding vectorIt can be expressed as

Wherein, α > 0 is regularization parameter, G_l=[g_1,l g_2,l … g_K,l],For power factor, believe so that sending Number x_k,lMeet corresponding power constraints, under total power constraint, power factorAre as follows:

Here by taking total power constraint as an example, but it is not limited to total power constraint, for other power constraints, setting Corresponding power factor β.

(2) wave beam divides multiple access transmission method

Wave beam divide multiple access transmission method be light sending node according to channel information be different light-receiving node distribution mutually not The transmission beam set of overlapping sends the signal of different light-receiving nodes using different transmission beam sets.Specifically, l A light sending node sends signal x to k-th of light-receiving node_k,lCovariance matrix beWhen light is sent out When sending element number larger, each smooth transmission unit sends mutually independent signal in Beam Domain, i.e. transmission signal covariance Matrix Q_k,lFor diagonal matrix, diagonal entry indicates the transmission power of each smooth transmission unit, is obtained by following power distribution algorithm It arrives.

Step 1, first of smooth sending node (l=1,2 ..., L) is k-th of light-receiving node in idle beam set In select the maximum wave beam of channel gain, i.e. b_k,l=argmax_jh_k,l,j, beam gain is denoted as

Step 2, initialization sends signal covariance matrixThe number of iterations i=1, system and rate R⁽⁰⁾=0.

Step 3, for first of smooth sending node, the power distribution of other light sending nodes is fixed, utilizes water-filling algorithm meter It calculates to the transmission power that k-th of light-receiving node sends signal and is

Wherein, μ_lFor auxiliary variable, meet power constraints

Step 4, computing system and rate are

Step 5, if | R⁽ⁱ⁾-R^(i-1)| i=i+1, return step 3 is arranged in > ∈ (∈ is setting threshold value)；Otherwise, eventually Only iteration.

(3) method of reseptance based on MRC or MMSE linear receiver

Each light-receiving node receives the sum of the transmission signal of all smooth sending nodes, is arrived according to sending node of not sharing the same light Its channel state information is detected to signal is received, and restores the transmission signal of sending node of not sharing the same light.Specifically, k-th of light Receiving node receives the sum of the transmission signal of L light sending node y_k, utilize received vector r_k,lIt detects first of light and sends section The transmission signal of point, i.e.,

Received vector r_k,lAccording to equivalent channelIt is designed, considers two kinds of common linear recipients Case, i.e. maximum-ratio combing (MRC) and least mean-square error (MMSE) detection.For MRC scheme, received vector are as follows:

For MMSE detection scheme, received vector are as follows:

Wherein,σ²For noise variance.K-th of light-receiving node is to testing result r_k,lIt is decoded, restores originally transmitted signal, obtain the data information of first of smooth sending node.

(4) wave beam division multiple access method of reseptance

Wave beam division multiple access method of reseptance is light-receiving node according to light sending node to its channel information, is sent out for different light The node reception wave beam (light receiving unit) that distribution does not overlap set is sent, is connect using different reception wave beams (light receiving unit) Receive the transmission signal for sending node of not sharing the same light.Specific method of reseptance is as follows:

Step 1, light-receiving node is according to each smooth sending node to its channel information, and calculating does not share the same light sending node to different The channel gain of light receiving unit,And arrange it in descending order, the light receiving unit after arrangement indexes note For d_l=[d_l,1 d_l,2 … d_l,N], wherein d_l,1It indicates to receive first of smooth maximum light-receiving list of sending node signal power Member.

Step 2, it is γ and the corresponding maximum light receiving unit number of single light sending node that setting, which receives power threshold, For N_d, for first of smooth sending node, select reception setMeet N_lA light-receiving The reception power of unit is higher than threshold valueLight receiving unit number is less than maximum limitation number, N_l≤N_d, and it is different The receiving unit set of light sending node does not overlap,

Step 3, weighting coefficient is utilizedBy light receiving unit setReception signal into Row weighted sum, weighting coefficient can choose r_l,i=1, can also be according to power designs are received

Step 4, weighted signal is decoded, restores the transmission signal of light sending node.