CN105915472A - Artificial noise-based cooperative network power allocation method for main channel and cooperative channel under non ideal channel estimation condition - Google Patents

Abstract

The invention discloses an artificial noise-based cooperative network power allocation method for a main channel and a cooperative channel under a non ideal channel estimation condition. After a transmitting end uses legal communication main channel information obtained in a non ideal channel estimation method, a transmitting signal is designed, power allocation between a useful signal and an artificial noise signal is carried out, on the basis of ensuring the security performance, and useful secrecy messages are transmitted to a legal receiver as much as possible. In addition, in order to improve the security of the secrecy messages, a cooperative jammer (CJ) is added, the CJ uses cooperative channel information obtained in the non ideal channel estimation method to design a transmitting signal to jam an eavesdropping node Eva. Under the condition of only knowing the statistical channel information of an eavesdropping channel at the transmitting end, the system security transmission rate is maximized through optimizing power allocation for the transmitting signal at the transmitting end, and the most effective security transmission of the secrecy messages in the cooperative network is realized.

Description

Main channel and association based on man made noise under the conditions of the channel imperfect channel estimation that cooperates Make power distribution method in network

Technical field

The invention belongs to information technology security fields, particularly relate to a kind of main channel and the channel imperfect channel estimation that cooperates Under the conditions of power distribution method in collaborative network based on man made noise.

Background technology

Along with the development of wireless communication technology, information security technology based on physical layer resources has become radio communication and letter The study hotspot in two fields of breath safety.The multiformity of wireless communication system physical layer resource is the research of safety of physical layer technology Provide wide space, also leave many problem demanding prompt solutions.Over nearly 10 years, the physical-layer techniques in radio communication is fluffy The exhibition of breaking out, new technique emerges in an endless stream, and therefore, develops uniqueness and the confidentiality of physical layer resources the most fully, and physical layer is pacified The research of full technology has carried out deep exploration to it.

Currently, the basic research thinking of safety of physical layer technology has both direction.One, with under various tapping channel models Secrecy capacity analyze based on, main thought is if main channel is than the better reliability of tapping channel, it is possible to guarantee Reliable communication on one constant bit rate.This type of study in frequently with system performance index be secrecy capacity (Secrecy And secrecy interruption rate (Secrecy outage probability) Capacity). its two, in conjunction with traditional encryption thought, profit Produce, manage and distribute key by the feature of wireless channel, thus improve the safety of key management.This class research is to pass System information security technology research extension on a physical layer.

Cooperation interference (Cooperative jamming, CJ) technology is based on above-mentioned first research direction, in physical layer The branch that safe practice occurs after rising, its basic thought is by sending artificial noise and interference signal so that it is right The infringement of eavesdropping node is more than the impact on legitimate receiver, thus reaches to promote the purpose of security of system (as promoted secrecy Capacity or the interruption rate of eavesdropping node).The secrecy capacity of Gauss tapping channel is expressed as source node (Alice) destination node (Bob) mutual information eavesdrops the difference of the mutual information of node (Eve) with source node (Alice).Therefore, eavesdropping node is reduced Receptivity be also a kind of method promoting security of system.Such as " Outage Constrained Secrecy Rate Maximization Using Artificial-Noise Aided Beamforming and Cooperative Jamming " have studied on the basis of tapping channel model, introduce the 4th node and i.e. cooperate the model of interfering nodes, this joint Point is by sending artificial interference, and simultaneously in transmitting terminal transmitting portion man-made noise, reduces the reception Signal to Interference plus Noise Ratio of listener-in, Thus reach to promote the purpose of security of system in physical layer.But, current safe transmission design is based primarily upon and can obtain The hypothesis of the perfect channel estimation of channel condition information.But in actual application, this hypothesis is the most unreasonable.

It is all the situation of imperfect channel estimation for main channel and cooperation channel, estimates channel and the actual channel obtained Certainly existing error, therefore man made noise's vector sum of the emission source channel condition information design to estimate cooperates jammer to estimate The interference signal of the channel condition information design of meter is inevitable all can be impacted legitimate receiver, reduces the letter of legitimate receiver Dry ratio of making an uproar.Therefore, considering that main channel and cooperation channel study useful signal and people in the case of being all imperfect channel estimation Between work noise signal, reasonable power divides pair system physical security can have important impact.

Summary of the invention

It is an object of the invention to overcome the deficiencies in the prior art, it is provided that a kind of main channel and the channel non-ideal communication channel that cooperates Power distribution method in collaborative network based on man made noise under the conditions of estimation, sends interference letter by adding cooperation interference unit machine Number setting up cooperation relation, emission source and cooperation jammer utilizes imperfect channel estimation method to estimate the channel condition information obtained Signal, the safe transmission speed that system reaches after the channel that there is estimation difference are launched in design, and the safety calculating system passes Defeated speed；Calculating emission source again by optimizing the optimal power allocation obtained under the conditions of perfect channel estimation than design transmitting signal is The safe transmission speed of this system, and by its with perfect channel estimation under the conditions of security of system speed compare, checking considers The importance of channel estimation errors, proposes more reliable, actual power allocation scheme.

It is an object of the invention to be achieved through the following technical solutions: main channel and the channel imperfect channel estimation that cooperates Under the conditions of power distribution method in collaborative network based on man made noise, it comprises the following steps:

S1: legitimate receipt end sends pilot frequency sequence, described pilot frequency sequence to emission source transmitting terminal and cooperation jammer simultaneously Actual channel through transmitting terminal to legitimate receipt endSimultaneously through the actual channel of cooperation jammer to legitimate receipt end

S2: transmitting terminal and cooperation jammer receive pilot frequency sequence respectively and do imperfect channel estimation and obtain h_b、h_bc, the most in fact Error is there is in border channel with estimation channel,NoteWhereinRepresent the covariance matrix of random vector；

S3: transmitting terminal and cooperation jammer are utilized respectively estimation channel matrix h_b、h_bcDesign respective transmitting signal s, s_c；

Signal launched by S4: transmitting terminal and cooperation jammer simultaneously, and legitimate receipt end receives from actual channel's s、s_c, eavesdropping end is eavesdropped from tapping channel h_e、h_ecS, s_c；

The termination collection of letters number of S5: legitimate receipt is y_bAnd calculate Signal to Interference plus Noise Ratio, it is expressed as γ_b(φ), according to launching setting of signal Meter principle understandsSimplified expression, the reception signal of legitimate receipt end is expressed as

$\begin{array}{c}{y}_b={\left({b_b}^{\′}\right)}^{H}s+{\left({h_{bc}}^{\′}\right)}^H{s}_c+n_b\\ ={\left(h_b-{\mathrm{\δ}}_b\right)}^{H}s+h_{bc}^H{s}_c+n_b\\ =h_b^{H}s-{\mathrm{\δ}}_b^{H}s+h_{bc}^H{s}_c+n_b\\ =h_b^{H}s-{\mathrm{\δ}}_b^{H}s+n_b\end{array}$

Wherein, n_b,n_e～CN (0,1) represents noise respectively on legal receiving terminal and the impact of eavesdropping end；Transmitting terminal launches letter Man made noise's signal section reply legitimate receipt end in number s does not has any impact, therefore meets:

$s=\sqrt{P_a\mathrm{\φ}}vx+\sqrt{\frac{P_a(1-\mathrm{\φ})}{N_a-1}}{N}_{v}n$

Wherein, P_aRepresent the transmit power constraint of transmitting terminal；φ ∈ [0,1] represents P_aPower-division ratios；X～CN (0,1) WithRepresent data signal and the Gaussian noise vector of Gauss code book respectively, and be separate；Equation The right Section 1 represents the axial signal of information, whereinSection 2 represents man made noise's vector, whereinColumn vector constituteThe orthonormal basis of kernel；

Jammer end launches signal s_cReply legitimate receiver does not has any impact, i.e. yetSo s_cIt is expressed as

$s_c=\sqrt{\frac{P_c}{N_c-1}}Wz$

Wherein P_cRepresent the transmit power constraint of CJ；The column vector of W definesThe orthonormal basis of kernel；Represent a Gaussian noise vector；

The letter of legitimate receipt end is dried and can be expressed as than SINR

${\mathrm{\γ}}_b\left(\mathrm{\φ}\right)=\frac{P_a\mathrm{\φ}\left|\right|h_b|{|}^2}{1+\frac{P_a(1-\mathrm{\φ})}{N_a-1}|{\mathrm{\δ}}_b^H{N}_{vb}{|}^2+\frac{P_c}{N_c-1}|\left|{\mathrm{\δ}}_{bc}^H{W}_{bc}\right|{|}^2}$

KnownAndColumn vector constituteZero empty Between orthonormal basis, W_bcColumn vector defineThe orthonormal basis of kernel, thus obtain Therefore:

${\mathrm{\γ}}_b\left(\mathrm{\φ}\right)=\frac{P_a\mathrm{\φ}\left|\right|h_b|{|}^2}{1+\frac{P_a(1-\mathrm{\φ})}{N_a-1}{\mathrm{\σ}}_1+\frac{P_c}{N_c-1}{\mathrm{\σ}}_2}={\mathrm{\γ}}_c\left(\mathrm{\φ}\right)\mathrm{\φ}$

${\mathrm{\γ}}_c\left(\mathrm{\φ}\right)=\frac{P_a\left|\right|h_b|{|}^2}{1+\frac{P_a(1-\mathrm{\φ})}{N_a-1}{\mathrm{\σ}}_1+\frac{P_c}{N_c-1}{\mathrm{\σ}}_2}$

Only know that due to system the statistical information of tapping channel, the reception signal of eavesdropping end and Signal to Interference plus Noise Ratio are still preferable letter Result under the conditions of road estimation, is respectively as follows:

$y_e=h_e^{H}s+h_{ec}^H{s}_c+n_e;$

${\mathrm{\γ}}_e\left(\mathrm{\φ}\right)=\frac{P_a\mathrm{\φ}\left|\right|h_e^{H}v|{|}^2}{1+\frac{P_a(1-\mathrm{\φ})}{N_a-1}|h_e^H{N}_v{|}^2+\frac{P_c}{N_c-1}|\left|h_{ec}^{H}W\right|{|}^2};$

Security interrupt maximum capacity to be realized, this optimization problem can be equivalent to a power distribution problems, describes such as Under:

$\begin{array}{cc}\underset{0\≤\mathrm{\φ}\≤1}{\max }& R_s={\log }_2\left(\frac{1+\mathrm{\γ}\mathrm{\φ}}{1+\mathrm{\μ}}\right)\\ s.t.& \mathrm{Pr}\left({\mathrm{\γ}}_e\left(\mathrm{\φ}\right)>\mathrm{\μ}\right)=\mathrm{\ϵ},\\ & 0\≤R_s\≤C_b.\end{array}$

Wherein γ=P_a||h_b||², R_sRepresenting safe transmission speed, ε represents security interrupt probability constraints, C_b=log₂(1+ γ_b(φ) channel capacity of main channel) is represented,Represent the threshold value relevant with outage probability；

Solving security interrupt probability constraints is:

$ln\left(\frac{1}{\mathrm{\ϵ}}\right)=\frac{\mathrm{\ω}}{P_a}+ln\[1+(1-\mathrm{\φ})\mathrm{\ω}\]+3ln(1+\frac{\mathrm{\ω}}{d})$

WhereinWithFound out that ω is an implicit function about φ by above formula, and obviously ω (φ) ＞ 0, then the formula of power distribution problems means that into:

$R_s={\log }_2\left(\frac{1+{\mathrm{\φ\γ}}_c\left(\mathrm{\φ}\right)}{1+\mathrm{\φ}\mathrm{\ω}\left(\mathrm{\φ}\right)}\right);$

S6: calculate optimum allocation when maximum safe transmission speed under the conditions of perfect channel estimation, i.e. use numerical analysis side Method solution formulaOptimal power allocation during optimization is than φ * and maximum safe transmission speed R_s ^*；

S7: Optimal Ratio φ * under the conditions of perfect channel estimation is substituted into last formula in step S4 and obtains R_s'= R_s(φ *), observes and press the transmitting signal process and modelled signal that optimal power allocation designs than φ * under the conditions of perfect channel estimation Safe transmission speed R that when channel information used exists the channel of estimation difference, system can reach_s'；

Under the conditions of the estimation of S8: more satisfactory channel, optimal power allocation is than system energy after the channel that there is estimation difference Safe transmission speed R reached_s' with maximum safe transmission speed R that ideally can reach_s ^*, it was therefore concluded that.

The invention has the beneficial effects as follows: the invention provides a kind of main channel and the channel imperfect channel estimation condition that cooperates Under power distribution method in collaborative network based on man made noise, emission source and cooperation jammer have all taken into full account channel estimation There is the situation of estimation difference, emission source and cooperation jammer utilizes imperfect channel estimation method to estimate the channel status obtained Information design launches signal, takes into full account estimation difference during design, weakens interference signal and emission source that cooperation jammer is launched Launch the interference to legitimate receiver of the man made noise's vector in signal, reduce the Signal to Interference plus Noise Ratio that listener-in receives, thus improve The security performance of system.

Accompanying drawing explanation

Fig. 1 is the mode under the conditions of perfect channel estimation in collaborative network.

Fig. 2 is that in collaborative network, between Alice and CJ to Bob, channel all exists the mode of estimation difference.

Fig. 3 is the safety speed that between Alice and CJ to Bob, channel all exists error estimation and complete perfect channel estimation model The comparison of rate.

Detailed description of the invention

Technical scheme is described in further detail below in conjunction with the accompanying drawings:

Main channel and transmitting power in collaborative network based on man made noise under the conditions of the channel imperfect channel estimation that cooperates Distribution method, as shown in Figure 1, it is assumed that emission source Alice, to legitimate receiver Bob transmission security message, exists one in system This message is eavesdropped by passive eavesdropping node Eve, and another node CJ launches signal to eavesdropping joint as cooperation jammer Point Eve interferes.Emission source Alice launch be combined with imperfect channel estimation obtain legitimate correspondence channel (Alice with Communication channel between Bob, also known as main channel) information divides carrying out optimal power between useful signal and man made noise's AN signal Joining signal, wherein man made noise disturbs Eve thus reduces the signal to noise ratio that Eve end receives, and as much as possible to legitimate receiver Bob sends useful private message, and CJ combines cooperation channel (channel between CJ and the Bob) information of imperfect channel estimation simultaneously Design interference signal, with all strength interference Eve and on Bob without impact, make security of system transfer rate reach maximum, it is achieved that wireless network The maximally effective safe transmission of private message in network.

Hypothesized model is multiple input single output model, and Alice is furnished with N_aRoot antenna, CJ is furnished with N_cRoot antenna number, andWith Eve is only furnished with single antenna, if main channel is usedRepresenting, cooperation channel is usedRepresent；Assume that Alice and CJ is only Knowing the statistical information of tapping channel, wherein the tapping channel of Alice and CJ to Eve is expressed asWherein h_eAnd h_ecSeparate and all obedience zero-mean Cyclic Symmetries answer Gauss distribution；When Alice wants When Bob sends a data stream, in order to stop Eve to intercept useful information, transmission signal power is distributed to useful by Alice Signal and man made noise's signal, CJ launches interference signal simultaneously.

First, it is considered to the when maximum safe transmission speed of the optimal power allocation under the conditions of perfect channel estimation.Alice pair Main channel is done perfect channel estimation and is obtained estimating channel information h_b, and design transmitting signal beCooperation channel is done by CJ Perfect channel estimation obtains estimating channel information h_bcAnd design transmitting signal beThe reception signal of Bob and Eve is respectively It is expressed as

$y_b=h_b^{H}s+h_{bc}^H{s}_c+n_b---\left(1\right)$

$y_e=h_e^{H}s+h_{ec}^H{s}_c+n_e---\left(2\right)$

Wherein, n_b,n_e～CN (0,1) represents the interchannel noise in the signal that Bob and Eve receives respectively.Alice design Launch the man made noise's signal section in signal s and Bob do not had any impact, therefore meet:

$s=\sqrt{P_a\mathrm{\φ}}vx+\sqrt{\frac{P_a(1-\mathrm{\φ})}{N_a-1}}{N}_{v}n---\left(3\right)$

Wherein, P_aRepresent the transmit power constraint of transmitting terminal Alice；φ ∈ [0,1] represents P_aPower-division ratios；X～CN (0,1) andRepresent data signal and the Gaussian noise vector of separate Gauss code book respectively.Equation is right Limit Section 1 represents the axial signal of information, i.e. the useful information that Alice sends to Bob, whereinOn the right of equation Binomial represents man made noise's vector, whereinColumn vector constituteThe orthonormal basis of kernel.

The transmitting signal s of CJ end design_cReply Bob does not results in interference, i.e. yetSo s_cIt is expressed as

$s_c=\sqrt{\frac{P_c}{N_c-1}}Wz---\left(4\right)$

Wherein P_cRepresent the transmit power constraint of CJ；The column vector of W definesThe orthonormal basis of kernel；Represent a Gaussian noise vector.

Under conditions of perfect channel estimation, the letter of Bob and Eve is dried ratio and can be expressed as

γ_b(φ)=P_aφ||h_b||² (5)

${\mathrm{\γ}}_e\left(\mathrm{\φ}\right)=\frac{P_a\mathrm{\φ}\left|\right|h_e^{H}v|{|}^2}{1+\frac{P_a(1-\mathrm{\φ})}{N_a-1}|h_e^H{N}_v{|}^2+\frac{P_c}{N_c-1}|\left|h_{ec}^{H}W\right|{|}^2}---\left(6\right)$

Security interrupt maximum capacity to be realized, this optimization problem can be equivalent to a power distribution problems, describes such as Under:

$\begin{array}{cc}\underset{0\≤\mathrm{\φ}\≤1}{\max }& R_s={\log }_2\left(\frac{1+\mathrm{\γ}\mathrm{\φ}}{1+\mathrm{\μ}}\right)\\ s.t.& \mathrm{Pr}\left({\mathrm{\γ}}_e\left(\mathrm{\φ}\right)>\mathrm{\μ}\right)=\mathrm{\ϵ},\\ & 0\≤R_s\≤C_b.\end{array}---\left(7\right)$

Wherein γ=P_a||h_b||², R_sRepresenting safe transmission speed, ε represents security interrupt probability constraints, C_b=log₂(1+ γ_b(φ) channel capacity of main channel) is represented,Represent the threshold value relevant with outage probability.

Solving security interrupt probability constraints is

$ln\left(\frac{1}{\mathrm{\ϵ}}\right)=\frac{\mathrm{\ω}}{P_a}+ln\[1+(1-\mathrm{\φ})\mathrm{\ω}\]+3ln(1+\frac{\mathrm{\ω}}{d})---\left(8\right)$

WhereinWithBe can be seen that ω is an implicit function about φ by formula (8), and aobvious So ω (φ) ＞ 0.Then formula (7) just can be expressed as

$R_s\left(\mathrm{\φ}\right)={\log }_2\left(\frac{1+\mathrm{\φ}\mathrm{\γ}}{1+\mathrm{\φ}\mathrm{\ω}\left(\mathrm{\φ}\right)}\right)---\left(9\right)$

Owing to ω (φ) can not be expressed as closed form, we will divide with the optimal power of numerical analysis method solution formula (9) Proportioning φ * and maximum safe transmission speed R_s ^*。

The present invention comprises the steps:

S1: legitimate receiver Bob simultaneously sends pilot frequency sequence to emission source Alice and CJ, pilot frequency sequence respectively through The actual main channel of Alice to BobActual cooperation channel with CJ to Bob

S2:Alice and CJ receives pilot frequency sequence respectively and does imperfect channel estimation and obtain h_b、h_bc, i.e. actual channel with Estimate that channel exists error,NoteWherein Represent the covariance matrix of random vector.

S3:Alice and CJ is utilized respectively estimation channel matrix h_b、h_bcDesign respective transmitting signal s, s_c。

S4:Alice and CJ launches signal simultaneously, and Bob receives from actual channelS, s_c, Eve eavesdropping from Tapping channel h_e、h_ecS, s_c。

S5:Bob receives message y_b, calculate Signal to Interference plus Noise Ratio SINR, be expressed as γ_b(φ), former according to the design launching signal Then understandSimplified expression, Bob receives signal and is expressed as

$\begin{array}{c}{y}_b={\tilde{h}}_b^{H}s+{\tilde{h}}_{bc}^H{s}_c+n_b\\ ={\left(h_b+{\mathrm{\δ}}_b\right)}^{H}s+{\left(h_{bc}+{\mathrm{\δ}}_{bc}\right)}^H{s}_c+n_b\\ =h_b^{H}s+{\mathrm{\δ}}_b^{H}s+h_{bc}^H{s}_c+{\mathrm{\δ}}_{bc}^H{s}_c+n_b\\ =h_b^{H}s+{\mathrm{\δ}}_b^{H}s+{\mathrm{\δ}}_{bc}^H{s}_c+n_b\end{array}---\left(10\right)$

The letter of Bob is dried and is expressed as than SINR

${\mathrm{\γ}}_b\left(\mathrm{\φ}\right)=\frac{P_a\mathrm{\φ}\left|\right|h_b|{|}^2}{1+\frac{P_a(1-\mathrm{\φ})}{N_a-1}|{\mathrm{\δ}}_b^H{N}_{vb}{|}^2+\frac{P_c}{N_c-1}|\left|{\mathrm{\δ}}_{bc}^H{W}_{bc}\right|{|}^2}---\left(11\right)$

KnownAndColumn vector constituteZero empty Between orthonormal basis, W_bcColumn vector defineThe orthonormal basis of kernel, thus obtain Therefore

${\mathrm{\γ}}_b\left(\mathrm{\φ}\right)=\frac{P_a\mathrm{\φ}\left|\right|h_b|{|}^2}{1+\frac{P_a(1-\mathrm{\φ})}{N_a-1}{\mathrm{\σ}}_1+\frac{P_c}{N_c-1}{\mathrm{\σ}}_2}={\mathrm{\γ}}_c\left(\mathrm{\φ}\right)\mathrm{\φ}---\left(12\right)$

${\mathrm{\γ}}_c\left(\mathrm{\φ}\right)=\frac{P_a\left|\right|h_b|{|}^2}{1+\frac{P_a(1-\mathrm{\φ})}{N_a-1}{\mathrm{\σ}}_1+\frac{P_c}{N_c-1}{\mathrm{\σ}}_2}---\left(13\right)$

Due to, this system only knows the statistical information of tapping channel, the tapped signal of Eve still with perfect channel estimation condition Under the method for expressing of tapped signal the same, be still formula (2), therefore the SINR of Eve is the most constant, is expressed as formula (6).Safety Outage probability constraint is only the most relevant to tapping channel, therefore security interrupt constraints is constant, then under security interrupt probability constraints be System safe rate is represented by about the relation of the power-division ratios launching signal

$R_s={\log }_2\left(\frac{1+{\mathrm{\φ\γ}}_c\left(\mathrm{\φ}\right)}{1+\mathrm{\φ}\mathrm{\ω}\left(\mathrm{\φ}\right)}\right)---\left(14\right)$

S6: calculate optimum allocation when maximum safe transmission speed under the conditions of perfect channel estimation, i.e. use numerical analysis side Optimal power allocation during method solution formula (9) optimization is than φ * and maximum safe transmission speed R_s ^*。

S7: Optimal Ratio φ * under the conditions of perfect channel estimation is substituted into formula (14) and obtains R_s'=R_s(φ *), permissible Observe optimal power allocation under the conditions of pressing perfect channel estimation and launch signal through the letter used with modelled signal than what φ * designed Safe transmission speed R that when road information exists the channel of estimation difference, system can reach_s'。

Under the conditions of the estimation of S8: more satisfactory channel, optimal power allocation is than system energy after the channel that there is estimation difference Safe transmission speed R reached_s' with maximum safe transmission speed R that ideally can reach_s ^*, it was therefore concluded that.

The estimation used with modelled signal in view of the actual legitimate channel launching signal process in described step S5 There is estimation difference in channel, then the reception signal of Bob has change.Bob receives message y_b, calculate Signal to Interference plus Noise Ratio SINR, be expressed as γ_b(φ), according to the design principle launching signalSimplified expression, Bob receives signal and is expressed as

$\begin{array}{c}{y}_b={\tilde{h}}_b^{H}s+{\tilde{h}}_{bc}^H{s}_c+n_b\\ ={\left(h_b+{\mathrm{\δ}}_b\right)}^{H}s+{\left(h_{bc}+{\mathrm{\δ}}_{bc}\right)}^H{s}_c+n_b\\ =h_b^{H}s+{\mathrm{\δ}}_b^{H}s+h_{bc}^H{s}_c+{\mathrm{\δ}}_{bc}^H{s}_c+n_b\\ =h_b^{H}s+{\mathrm{\δ}}_b^{H}s+{\mathrm{\δ}}_{bc}^H{s}_c+n_b\end{array}---\left(10\right)$

The letter of Bob is dried and is expressed as than SINR

${\mathrm{\γ}}_b\left(\mathrm{\φ}\right)=\frac{P_a\mathrm{\φ}\left|\right|h_b|{|}^2}{1+\frac{P_a(1-\mathrm{\φ})}{N_a-1}|{\mathrm{\δ}}_b^H{N}_{vb}{|}^2+\frac{P_c}{N_c-1}|\left|{\mathrm{\δ}}_{bc}^H{W}_{bc}\right|{|}^2}---\left(11\right)$

KnownAndColumn vector constituteZero empty Between orthonormal basis, W_bcColumn vector defineThe orthonormal basis of kernel, thus obtain Therefore

${\mathrm{\γ}}_b\left(\mathrm{\φ}\right)=\frac{P_a\mathrm{\φ}\left|\right|h_b|{|}^2}{1+\frac{P_a(1-\mathrm{\φ})}{N_a-1}{\mathrm{\σ}}_1+\frac{P_c}{N_c-1}{\mathrm{\σ}}_2}={\mathrm{\γ}}_c\left(\mathrm{\φ}\right)\mathrm{\φ}---\left(12\right)$

${\mathrm{\γ}}_c\left(\mathrm{\φ}\right)=\frac{P_a\left|\right|h_b|{|}^2}{1+\frac{P_a(1-\mathrm{\φ})}{N_a-1}{\mathrm{\σ}}_1+\frac{P_c}{N_c-1}{\mathrm{\σ}}_2}---\left(13\right)$

Due to, this system only knows the statistical information of tapping channel, the tapped signal of Eve still with perfect channel estimation condition Under the method for expressing of tapped signal the same, be still formula (2), therefore the SINR of Eve is the most constant, is expressed as formula (6).Safety Outage probability constraint is only the most relevant to tapping channel, therefore security interrupt constraints is constant, then under security interrupt probability constraints be System safe rate is represented by about the relation of the power-division ratios launching signal

$R_s={\log }_2\left(\frac{1+{\mathrm{\φ\γ}}_c\left(\mathrm{\φ}\right)}{1+\mathrm{\φ}\mathrm{\ω}\left(\mathrm{\φ}\right)}\right)---\left(14\right)$

Setting antenna parameter Na=2, Nc=4, ε=0.1, | | h_b||²=1, the estimation difference taked is σ₁=σ₂=0.1, And consider P respectively_c=0dB and P_cTwo kinds of situations of=10dB.Find optimal solution by MATLAB emulation and contrast mapping, as Shown in Fig. 3, present in figure is under different condition, security of system speed and total pass launched between power of emission source Alice System, it can be clearly seen that channel h_b、h_bcWhen all there is estimation difference, the impact on the safe rate of system is channel h_b、h_bcRespectively When only one of which exists estimation difference affect security of system speed is comprehensive.The peace of system under conditions of perfect channel estimation Full rate increases with the increase launching power；And the safe rate of system is with launching merit under conditions of imperfect channel estimation The increase first increases and then decreases of rate, it is hereby achieved that the maximum of a safe rate.Analyze concrete data to understand:

(1) when the transmitting power of CJ end is 10dB, the change that the safe rate of system launches power with Alice end presents Going out the change of obvious first increases and then decreases, when the transmitting power of transmitting terminal is 13dB, safe rate reaches to be about 1.135bpcu (bit/channel uses).

(2) when the transmitting power of CJ end is 0dB, the change that the safe rate of system launches power with Alice end is failed to understand Aobvious, when the transmitting power of transmitting terminal is 14dB, safe rate reaches to be about 0.274bpcu (bit/channel uses).

The invention provides a kind of main channel and association based on man made noise under the conditions of the channel imperfect channel estimation that cooperates Make transmitting power division method in network, emission source and cooperation jammer and all taken into full account that channel is estimated to there is estimation difference Letter is launched in the channel condition information design that situation, emission source and cooperation jammer utilize imperfect channel estimation method to estimate to obtain Number, taking into full account estimation difference during design, the interference signal and the emission source that weaken cooperation jammer transmitting launch the people in signal The interference to legitimate receiver of the work noise vector, reduces the Signal to Interference plus Noise Ratio that listener-in receives, thus improves the security performance of system.

Emission source launches signal, Jing Guocun by optimizing the optimal power allocation obtained under the conditions of perfect channel estimation than design The safe transmission speed that system reaches after the channel of estimation difference, compares this safe transmission speed and perfect channel estimation condition The gap of lower security of system speed, checking considers the importance of channel estimation errors.Main channel and cooperation channel are taken into full account Channel estimation methods there is the situation of estimation difference, it is proposed that the actual power allocation scheme realizing security of system so that The security system set up can be applied in actual scene.

Claims (1)

1. main channel and power distribution side in collaborative network based on man made noise under the conditions of the channel imperfect channel estimation that cooperates Method, it is characterised in that: it comprises the following steps:

S1: legitimate receipt end sends pilot frequency sequence to emission source transmitting terminal and cooperation jammer simultaneously, and described pilot frequency sequence passes through Transmitting terminal is to the actual channel of legitimate receipt endSimultaneously through the actual channel of cooperation jammer to legitimate receipt end

S2: transmitting terminal and cooperation jammer receive pilot frequency sequence respectively and do imperfect channel estimation and obtain h_b、h_bc, Error is there is in i.e. actual channel with estimation channel,NoteWhereinRepresent the covariance matrix of random vector；

S3: transmitting terminal and cooperation jammer are utilized respectively estimation channel matrix h_b、h_bcDesign respective transmitting signal s, s_c；

Signal launched by S4: transmitting terminal and cooperation jammer simultaneously, and legitimate receipt end receives from actual channelS, s_c, Eavesdropping end is eavesdropped from tapping channel h_e、h_ecS, s_c；

The termination collection of letters number of S5: legitimate receipt is y_bAnd calculate Signal to Interference plus Noise Ratio, it is expressed as γ_b(φ), former according to the design launching signal Then understandSimplified expression, the reception signal of legitimate receipt end is expressed as

$\begin{array}{c}{y}_b={\left({h_b}^{\′}\right)}^{H}s+{\left({h_{bc}}^{\′}\right)}^H{s}_c+n_b\\ ={\left(h_b-{\mathrm{\δ}}_b\right)}^{H}s+h_{bc}^H{s}_c+n_b\\ =h_b^{H}s-{\mathrm{\δ}}_b^{H}s+h_{bc}^H{s}_c+n_b\\ =h_b^{H}s-{\mathrm{\δ}}_b^{H}s+n_b\end{array}$

Wherein, n_b,n_e～CN (0,1) represents noise respectively on legal receiving terminal and the impact of eavesdropping end；Transmitting terminal launches signal s In man made noise's signal section reply legitimate receipt end there is no any impact, therefore meet:

$s=\sqrt{P_a\mathrm{\φ}}vx+\sqrt{\frac{P_a(1-\mathrm{\φ})}{N_a-1}}{N}_{v}n$

Wherein, P_aRepresent the transmit power constraint of transmitting terminal；φ ∈ [0,1] represents P_aPower-division ratios；X～CN (0,1) andRepresent data signal and the Gaussian noise vector of Gauss code book respectively, and be separate；Equation is right Limit Section 1 represents the axial signal of information, whereinSection 2 represents man made noise's vector, whereinColumn vector constituteThe orthonormal basis of kernel；

Jammer end launches signal s_cReply legitimate receiver does not has any impact, i.e. yetSo s_cIt is expressed as

$s_c=\sqrt{\frac{P_c}{N_c-1}}Wz$

Wherein P_cRepresent the transmit power constraint of CJ；The column vector of W definesThe orthonormal basis of kernel；Represent a Gaussian noise vector；

The letter of legitimate receipt end is dried and can be expressed as than SINR

${\mathrm{\γ}}_b\left(\mathrm{\φ}\right)=\frac{P_a\mathrm{\φ}\left|\right|h_b|{|}^2}{1+\frac{P_a\left(1-\mathrm{\φ}\right)}{N_a-1}|{\mathrm{\δ}}_b^H{N}_{vb}{|}^2+\frac{P_c}{N_c-1}|\left|{\mathrm{\δ}}_{bc}^H{W}_{bc}\right|{|}^2}$

KnownAndColumn vector constituteKernel Orthonormal basis, W_bcColumn vector defineThe orthonormal basis of kernel, thus obtain Therefore:

${\mathrm{\γ}}_b\left(\mathrm{\φ}\right)=\frac{P_a\mathrm{\φ}\left|\right|h_b|{|}^2}{1+\frac{P_a(1-\mathrm{\φ})}{N_a-1}{\mathrm{\σ}}_1+\frac{P_c}{N_c-1}{\mathrm{\σ}}_2}={\mathrm{\γ}}_c\left(\mathrm{\φ}\right)\mathrm{\φ}$

${\mathrm{\γ}}_c\left(\mathrm{\φ}\right)=\frac{P_a\left|\right|h_b|{|}^2}{1+\frac{P_a(1-\mathrm{\φ})}{N_a-1}{\mathrm{\σ}}_1+\frac{P_c}{N_c-1}{\mathrm{\σ}}_2}$

Only know the statistical information of tapping channel due to system, reception signal and the Signal to Interference plus Noise Ratio of eavesdropping end are still estimated for ideal communication channel Result under the conditions of meter, is respectively as follows:

$y_e=h_e^{H}s+h_{ec}^H{s}_c+n_e;$

${\mathrm{\γ}}_e\left(\mathrm{\φ}\right)=\frac{P_a\mathrm{\φ}|h_e^{H}v{|}^2}{1+\frac{P_a(1-\mathrm{\φ})}{N_a-1}|h_e^H{N}_v{|}^2+\frac{P_c}{N_c-1}|\left|h_{ec}^{H}W\right|{|}^2};$

Security interrupt maximum capacity to be realized, this optimization problem can be equivalent to a power distribution problems, be described as follows:

$\begin{array}{cc}\underset{0\≤\mathrm{\φ}\≤1}{max}& R_s={\log }_2\left(\frac{1+\mathrm{\γ}\mathrm{\φ}}{1+\mathrm{\μ}}\right)\end{array}$

s.t. Pr(γ_e(φ) ＞ μ)=ε,

0≤R_s≤C_b.

Wherein γ=P_a||h_b||², R_sRepresenting safe transmission speed, ε represents security interrupt probability constraints, C_b=log₂(1+γ_b (φ) channel capacity of main channel) is represented,Represent the threshold value relevant with outage probability；

Solving security interrupt probability constraints is:

$ln\left(\frac{1}{\mathrm{\ϵ}}\right)=\frac{\mathrm{\ω}}{P_a}+ln\[1+(1-\mathrm{\φ})\mathrm{\ω}\]+3ln(1+\frac{\mathrm{\ω}}{d})$

WhereinWithFound out that ω is an implicit function about φ by above formula, and obviously ω (φ) ＞ 0, Then the formula of power distribution problems means that into:

$R_s={\log }_2\left(\frac{1+{\mathrm{\φ\γ}}_c\left(\mathrm{\φ}\right)}{1+\mathrm{\φ}\mathrm{\ω}\left(\mathrm{\φ}\right)}\right);$

S6: calculate optimum allocation when maximum safe transmission speed under the conditions of perfect channel estimation, i.e. ask with numerical analysis method Solution formulaOptimal power allocation during optimization is than φ * and maximum safe transmission speed R_s ^*；

S7: Optimal Ratio φ * under the conditions of perfect channel estimation is substituted into last formula in step S4 and obtains R_s'=R_s (φ *), observes the transmitting signal process designed than φ * by optimal power allocation under the conditions of perfect channel estimation and makes with modelled signal Channel information safe transmission speed R that system can reach when there is the channel of estimation difference_s'；

Under the conditions of S8: more satisfactory channel is estimated, optimal power allocation can reach than system after the channel that there is estimation difference Safe transmission speed R_s' with maximum safe transmission speed R that ideally can reach_s ^*, it was therefore concluded that.