CN103067042B - A kind of secret communication method and antenna equipment - Google Patents
A kind of secret communication method and antenna equipment Download PDFInfo
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- CN103067042B CN103067042B CN201210545677.4A CN201210545677A CN103067042B CN 103067042 B CN103067042 B CN 103067042B CN 201210545677 A CN201210545677 A CN 201210545677A CN 103067042 B CN103067042 B CN 103067042B
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Abstract
The embodiment of the present invention provides a kind of secret communication method and antenna equipment, be applied to multi-antenna, described method comprises: according to the channel hopping speed in preset wireless channel saltus step rule, determines the channel hopping number of times of the modulation symbol of current time within the transmission cycle of this symbol; From in the preliminary treatment weights set preset wireless channel saltus step rule, choose the preliminary treatment weights of current time and the corresponding number of described channel hopping number of times; According to selected preliminary treatment weights, preliminary treatment is carried out to described modulation symbol, generate and send signal; Within the transmission cycle of described transmission signal, according to the channel hopping order in preset wireless channel saltus step rule, and the aerial information that described channel hopping is corresponding, in the process of transmitting sending signal, carry out the channel hopping with the corresponding number of times of described channel hopping number of times, complete the transmission sending signal.The embodiment of the present invention utilizes spatial domain channel fast to switch and achieves secure communication.
Description
Technical field
The present invention relates to communication technical field, more particularly, relate to a kind of secret communication method and antenna equipment.
Background technology
Along with fast development and the extensive use of wireless communication technology, a large amount of Wireless Telecom Equipments is flooded with daily life and becomes a requisite part gradually.But proper radio communication bring many simultaneously easily, the fail safe of private information transmission is also subject to people's attention further.Due to broadcast characteristic and the opening of wireless transmission, compared with wire communication, radio communication suffers more severe security threat.In existing safety measure, mostly adopt the data encryption realized based on computation complexity at protocol high layer machine-processed.But the mobility had due to radio communication and the dynamic change of network topology, conventional cryptography mechanism faces a difficult problem for key management and distribution.Therefore, in the urgent need to seeking brand-new safety measure to tackle the safety problem of radio communication.
In fact, the wireless transmission medium lacking border constraint is the Advantages found of radio communication and the inducement place of security threat generation.Only have first " security protection " (physical layer) to radio communication, take effective safety measure fundamentally could solve the safety problem of radio communication; Existing frequency hopping, when jumping and the technology such as direct sequence spread spectrum attempt to improve from physical layer the fail safe of radio communication, to prevent listener-in to the eavesdropping of transmission data.But existing frequency hopping, Time-Hopping are the quick switchings based on running time-frequency resource, it requires that the switching of running time-frequency resource has enough speed and width, owing to being subject to the constraint of system and available time-frequency domain resources, the switching degree of freedom of frequency or time is limited often, listener-in still can the useful information of fetching portion running time-frequency resource to sending that signal carries out after long-term observation statistics, and this makes to transmit data and there is the larger hidden danger that is stolen.
Summary of the invention
In view of this, the embodiment of the present invention provides a kind of secret communication method and equipment, limits with the switching solved due to time-frequency domain resources, and makes to transmit the problem that data exist the larger hidden danger that is stolen.
For achieving the above object, the embodiment of the present invention provides following technical scheme:
A kind of secret communication method, be applied to multi-antenna, described method comprises:
According to the channel hopping speed in preset wireless channel saltus step rule, determine the channel hopping number of times of the modulation symbol of current time within the transmission cycle of this symbol;
From in the preliminary treatment weights set preset wireless channel saltus step rule, choose the preliminary treatment weights of current time and the corresponding number of described channel hopping number of times;
According to selected preliminary treatment weights, preliminary treatment is carried out to described modulation symbol, generate and send signal;
Within the transmission cycle of described transmission signal, according to the channel hopping order in preset wireless channel saltus step rule, and the aerial information that described channel hopping is corresponding, in the process of transmitting sending signal, carry out the channel hopping with the corresponding number of times of described channel hopping number of times, complete the transmission sending signal.
Wherein, described according to the channel hopping order in preset wireless channel saltus step rule, and the aerial information that described channel hopping is corresponding, in the process of transmitting sending signal, carry out comprising with the process of the channel hopping of the corresponding number of times of described channel hopping number of times:
Be the signal segment with the corresponding number of described channel hopping number of times by described transmission division of signal, according to the sequencing of the channel hopping in preset wireless channel saltus step rule, each signal segment is sequentially dispensed to antenna corresponding to each channel hopping, each respective antenna sequentially sends each signal segment, completes the transmission sending signal.
Wherein, the set of described preliminary treatment weights comprises: the multiple random vector changing modulation symbol width/phase modulation intelligence, and/or, select the gating variable of transmitting antenna.
Wherein, described method also comprises: the recipient to described transmission signal sends pilot frequency sequence, so that described recipient estimates the channel gain coefficient between the transmit leg of described transmission signal and recipient;
When transmission receiving side signal is multi-antenna, also comprise: signal extension process is carried out to described modulation symbol, to transmit multi-stream information on multiple antennas simultaneously.
The embodiment of the present invention also provides a kind of secret communication method, comprising:
The transmission signal that Received signal strength transmit leg is sent by multiple antennas;
According to the channel hopping speed in preset wireless channel saltus step rule, determine to send channel hopping number of times corresponding to signal;
According to the preliminary treatment weights set in preset wireless channel saltus step rule, and the channel hopping number of times of described correspondence, determine to send signal at preliminary treatment weights corresponding to delivery time;
According to determined preliminary treatment weights, demodulation coding is carried out to described transmission signal, generate modulation symbol.
Wherein, described method also comprises:
The pilot frequency sequence that the transmit leg receiving described transmission signal sends, so that the channel gain coefficient between the transmit leg of estimation and described transmission signal.
The embodiment of the present invention also provides a kind of antenna equipment, and described antenna equipment is multi-antenna, comprising:
Channel hopping number of times determination module, for according to the channel hopping speed in preset wireless channel saltus step rule, determines the channel hopping number of times of the modulation symbol of current time within the transmission cycle of this symbol;
Preliminary treatment weights choose module, for from the preliminary treatment weights set in preset wireless channel saltus step rule, choose the preliminary treatment weights of current time and the corresponding number of described channel hopping number of times;
Pretreatment module, for according to selected preliminary treatment weights, carries out preliminary treatment to described symbol to be modulated, generates and sends signal;
Sending module, for within the transmission cycle of described transmission signal, according to the channel hopping order in preset wireless channel saltus step rule, and the aerial information that described channel hopping is corresponding, in the process of transmitting sending signal, carry out the channel hopping with the corresponding number of times of described channel hopping number of times, complete the transmission sending signal.
Wherein, described sending module comprises:
Division unit, for being the signal segment with the corresponding number of described channel hopping number of times by described transmission division of signal;
Allocation units, for the sequencing according to the channel hopping in preset wireless channel saltus step rule, are sequentially dispensed to antenna corresponding to each channel hopping by each signal segment;
Transmitting element, for sequentially sending each signal segment in each respective antenna, completes the transmission sending signal.
Wherein, the set of described preliminary treatment weights comprises: the multiple random vector changing modulation symbol width/phase modulation intelligence, and/or, select the gating variable of transmitting antenna;
Described equipment also comprises:
Pilot frequency sequence sending module, for sending pilot frequency sequence to the recipient of described transmission signal, so that described recipient estimates the channel gain coefficient between the transmit leg of described transmission signal and recipient;
Extension process module, for when transmission receiving side signal is multi-antenna, carries out signal extension process to described modulation symbol, to transmit multi-stream information on multiple antennas simultaneously.
The embodiment of the present invention also provides a kind of antenna equipment, comprising:
Receiver module, for the transmission signal that Received signal strength transmit leg is sent by multiple antennas;
Send signaling channel transition times determination module, for according to the channel hopping speed in preset wireless channel saltus step rule, determine to send channel hopping number of times corresponding to signal;
Send Signal Pretreatment weights determination module, for according to the preliminary treatment weights set in preset wireless channel saltus step rule, and the channel hopping number of times of described correspondence, determine to send signal at preliminary treatment weights corresponding to delivery time;
Demodulation coding module, for carrying out demodulation coding according to determined preliminary treatment weights to described transmission signal, generates modulation symbol.
Based on technique scheme, the secret communication method that the embodiment of the present invention provides, relies on multi-antenna, the saltus step rule that basis signal receiving-transmitting sides is made an appointment, signal transmitting and receiving both sides based on the quick switching of spatial domain channel, can realize at different spatial domains transmission modulation intelligence.The embodiment of the present invention is by utilizing spatial domain channel resource, the switching solved due to time-frequency domain resources limits, and make to transmit the problem that data exist the larger hidden danger that is stolen, with time-space domain channel resource, also there is the difference characteristic that time-frequency domain resources do not have, the wireless channel of different position, spatial domain has monopolizing characteristic, for the secrecy transmission of information further provides guarantee.
Accompanying drawing explanation
In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, be briefly described to the accompanying drawing used required in embodiment or description of the prior art below, 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 prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.
The flow chart of the secret communication method that Fig. 1 provides for the embodiment of the present invention;
The schematic diagram of the transmission signal that Fig. 2 provides for the embodiment of the present invention;
The flow chart of the secret communication method that Fig. 3 provides for the embodiment of the present invention;
The structured flowchart of the execution mode one of the communication system that Fig. 4 provides for the embodiment of the present invention;
The structured flowchart of the execution mode two of the communication system that Fig. 5 provides for the embodiment of the present invention;
The structured flowchart of the antenna equipment that Fig. 6 provides for the embodiment of the present invention;
The structured flowchart of the sending module that Fig. 7 provides for the embodiment of the present invention;
The another structured flowchart of the antenna equipment that Fig. 8 provides for the embodiment of the present invention;
The structured flowchart of the secret signalling that Fig. 9 provides for the embodiment of the present invention.
Embodiment
Main thought of the present invention utilizes spatial domain resource, realized the secure communication of data by the quick switching of spatial domain channel.Below in conjunction with the accompanying drawing in the embodiment of the present invention, be clearly and completely described the technical scheme in the embodiment of the present invention, obviously, described embodiment is only the present invention's part embodiment, instead of whole embodiments.Based on the embodiment in the present invention, those of ordinary skill in the art, not making the every other embodiment obtained under creative work prerequisite, belong to the scope of protection of the invention.
The flow chart of the secret communication method that Fig. 1 provides for the embodiment of the present invention, Fig. 1 describes with the angle of signalling the secret communication method that the embodiment of the present invention provides, the embodiment of the present invention requires that signalling has the antenna that many are carried out signal transmission, and with reference to Fig. 1, the method can comprise:
Step S100, according to the channel hopping speed in preset wireless channel saltus step rule, determine the channel hopping number of times of the modulation symbol of current time within the transmission cycle of this symbol;
Wherein, modulation symbol refers to undressed primary signal, and it is corresponding with the signal without time frequency processing in prior art.
Wireless channel saltus step rule can be that signalling and receiving side signal are made an appointment, undertaken arranging (as wireless channel saltus step rule copied respectively in the memory device of signal transmitting and receiving both sides by storage medium) by offline mode, the negotiation also can being carried out wireless channel saltus step rule by the secure transmission tunnel set up is mutual.
The available Ψ of wireless channel saltus step rule represents,
for the preliminary treatment weights set of modulation symbol, Γ is hopping sequence rule,
usually be made up of pseudo random sequence with Γ thus make the switching of spatial domain channel have pseudo-random characteristics.
Hopping sequence rule Γ can arrange switching (saltus step) speed of spatial domain channel simultaneously, first can determine the current time that modulation symbol sends, thus determine switching (saltus step) the speed r=1/t of the spatial domain channel of current time by the hopping sequence rule Γ of current time
c, wherein t
cfor the time (switching cycle, unit is second) of a certain selected preliminary treatment weights continuous action, namely signal is in the duration of channel corresponding to these preliminary treatment weights, if the transmitting time cycle of modulation symbol is T
s(second), then the number of times that in each modulation symbol interval, spatial domain channel switches is N=T
s/ t
c.Work as T
s=t
ctime, each modulation symbol performs a preliminary treatment, namely carries out a channel hopping between modulation symbol and modulation symbol, otherwise each modulation symbol segmentation sends after performing repeatedly preliminary treatment continuously, and namely each modulation symbol segmentation sends continuously on multiple antennas.
The channel hopping of embodiment of the present invention indication is, signal is skipped on another antenna by an antenna and sends.
Step S110, from the preliminary treatment weights set preset wireless channel saltus step rule, choose the preliminary treatment weights of current time and the corresponding number of described channel hopping number of times;
For the embodiment of the present invention, preliminary treatment weights can represent chooses the transmission that some antennas carry out signal from multiple antennas, and namely preliminary treatment weights can comprise the aerial information of multi-antenna; Also all antennas can be adopted to carry out signal transmission, whether represent the activation of current antenna with preliminary treatment weights.Optionally, in the embodiment of the present invention, the form of expression of preliminary treatment weights can be the multiple random vector of the width/phase modulation intelligence changing modulation symbol, and also can be the gating variable selecting transmitting antenna, also can be both combinations.
For multiple random vector, obtain by following manner: the hop rate r that can set according to hopping sequence rule Γ, if r=N, and the number N of transmitting antenna
t, produce matrix at random
singular value decomposition P=U ∑ V is carried out to this matrix
h, wherein
and V
n × Nbe respectively the left and right singular matrix of P and there is characteristic at the tenth of the twelve Earthly Branches.Therefore each column vector of U and V all can alternatively preliminary treatment weights.
For the gating variable of transmitting antenna, { 0,1}, wherein, 1 represents that the antenna of respective index is activated, and for sending signal, the antenna un-activation of 0 expression respective index, does not send signal can to establish W ∈.
Optionally, in order to keep the different decorrelation switching spatial domain channel, in the embodiment of the present invention, the generation of different pretreatments weights has irrelevance, realizes having pseudo-random characteristics when switching with sky line options.
Step S120, according to selected preliminary treatment weights, preliminary treatment is carried out to described modulation symbol, generate and send signal;
If the modulation symbol of current time n is x (n), selected preliminary treatment weight matrix is
the transmission signal then generated is S (n)=W (n) x (n), if channel hopping times N is greater than 1, then S (n) needs in the mark space that N number of time slice forms, and the symbol of each time slice group is sent by different antennas.
Transmission signal herein refers to the signal data that original modulation symbol is formed after treatment, and it is corresponding with the signal through time frequency processing.
Step S130, within the transmission cycle of described transmission signal, according to the channel hopping order in preset wireless channel saltus step rule, and the aerial information that described channel hopping is corresponding, in the process of transmitting sending signal, carry out the channel hopping with the corresponding number of times of described channel hopping number of times, complete the transmission sending signal.
The object that the embodiment of the present invention will realize is, the secrecy transmission of modulation symbol, and sending signal is the signal data formed after carrying out preliminary treatment to modulation symbol, its essence is when modulation symbol carries out channel hopping, carries out the prompting of target saltus step channel.Therefore the optional implementation of the one of step S130 can be: be the signal segment with the corresponding number of described channel hopping number of times by described transmission division of signal, according to the sequencing of the channel hopping in preset wireless channel saltus step rule, each signal segment is sequentially dispensed to antenna corresponding to each channel hopping, each respective antenna sequentially sends each signal segment, completes the transmission sending signal.As shown in Figure 2, send signal and be divided into N part signal segment, be respectively N1 ~ Nk, each signal segment comprises preliminary treatment weights of a symbol fragment and correspondence, signal segment is undertaken corresponding with preliminary treatment weights by signal hopping sequence, when signal sends, according to the sending order of signal segment (by N1 to NK, generally determined by the teaming method of signal, as data frame head be sent in before etc.), each signal segment is sequentially dispensed to corresponding antenna to send, completes the transmission sending signal.Obviously, also can comprise the routine operation such as pulse shaping, uppermixing in the process that signal sends, repeat no more herein.
The secret communication method that the embodiment of the present invention provides, relies on multi-antenna, the saltus step rule that basis signal receiving-transmitting sides is made an appointment, and signal transmitting and receiving both sides based on the quick switching of spatial domain channel, can realize at different spatial domains transmission modulation intelligence.The embodiment of the present invention is by utilizing spatial domain channel resource, the switching solved due to time-frequency domain resources limits, and make to transmit the problem that data exist the larger hidden danger that is stolen, with time-space domain channel resource, also there is the difference characteristic that time-frequency domain resources do not have, the wireless channel of different position, spatial domain has monopolizing characteristic, for the secrecy transmission of information further provides guarantee.
Optionally, because receiving side signal is in the process of carrying out signal receiving, need the channel gain coefficient related between receiving-transmitting sides, therefore method shown in Fig. 1 can also comprise: the recipient to described transmission signal sends pilot frequency sequence, so that described recipient estimates the channel gain coefficient between the transmit leg of described transmission signal and recipient; Optionally, corresponding channel training and method of estimation can be set signal transmitting and receiving both sides, the estimation mode of can be orthogonal sequence training method also can be space time processing.When wireless channel is slow fading channel, channel gain coefficient can be estimated with mark space, and when channel be in become soon time, channel estimating also will be estimated with the spatial domain channel switching interval time.
If send receiving side signal to also provided multiple antennas, so method shown in Fig. 1 supports multiple stream transmission, and method shown in Fig. 1 can also carry out signal extension process to modulation symbol, to transmit multi-stream information on multiple antennas simultaneously.
Below from the angle of receiving side signal, be described the secret communication method that the embodiment of the present invention provides, the method for following description is corresponding with method shown in Fig. 1.The flow chart of the secret communication method that Fig. 3 provides for the embodiment of the present invention, with reference to Fig. 3, the method can comprise:
The signal that step S200, Received signal strength transmit leg are sent by multiple antennas;
The signal of the embodiment of the present invention is transmitted by channel hopping mode, specifically can refer to the description to method shown in Fig. 1.
Due to the impact of channel gain, signal additive noise, the transmission signal received is Y (n)=H (n) S (n)+V (n), the wherein transmission signal that generates after preliminary treatment for modulation symbol of S (n), H (n) is road gain matrix, the additive noise that in the mark space that V (n) is signal delivery time n, different time fragment Received signal strength suffers.
Step S210, according to the channel hopping speed in preset wireless channel saltus step rule, determine to send channel hopping number of times corresponding to signal;
Wireless channel saltus step rule is made an appointment by signalling and receiving side signal, and the available Ψ of wireless channel saltus step rule represents,
for the set of modulation symbol preliminary treatment weights, Γ is hopping sequence rule,
usually be made up of pseudo random sequence with Γ thus make the switching of spatial domain channel have pseudo-random characteristics.Hopping sequence rule Γ has arranged switching (saltus step) the speed r=1/t of spatial domain channel simultaneously
c, by determining that channel hopping speed can determine channel hopping times N=T
s/ t
c.
Step S220, according to the preliminary treatment weights set in preset wireless channel saltus step rule, and the channel hopping number of times of described correspondence, determines to send signal at preliminary treatment weights corresponding to delivery time;
By the saltus step rule Ψ of agreement, can determine preliminary treatment weight matrix W (n) that delivery time n transmit leg adopts equally, the weights number in preliminary treatment weight matrix W (n) is corresponding with channel hopping number of times.
Step S230, according to determined preliminary treatment weights, demodulation coding is carried out to described transmission signal, generate modulation symbol.
After obtaining cicada W (n), due to S (n)=W (n) x (n), therefore can after learning H (n) and V (n), demodulation coding is carried out to signal Y (the n)=H (n) S (n)+V (n) received, generates original modulation symbol x (n).
Optionally, for learning H (n), method shown in Fig. 3 also should comprise step: the pilot frequency sequence receiving the transmit leg transmission sending signal, so that the channel gain coefficient between the transmit leg of estimation and transmission signal.For determining channel gain coefficient matrix H (n), signal transmitting and receiving both sides can arrange corresponding channel training and method of estimation, the estimation mode of can be orthogonal sequence training method also can be space time processing.When wireless channel is slow fading channel, H (n) can estimate with mark space, and when channel be in become soon time, channel estimating also will be estimated with the spatial domain channel switching interval time.In addition, recipient detects interpretation method can be that maximum likelihood or MMSE detect.
The embodiment of the present invention carries out the transmission of signal by the switching of spatial domain channel, when spatial domain hand-off process reaches given pace and does not have obvious statistical nature, for recipient, send signal and have passed through the transmission of similar randomizing channel, the fail safe of radio communication can be ensured.In addition, signal processing mode realizes channel and switches less to the hardware configuration dependence of system, and therefore spatial domain channel switches with traditional frequency hopping compared with Time-Hopping, can have higher switching rate, thus significantly improve the fail safe of system.
The secret communication method that theres is provided of embodiment for a better understanding of the present invention, provides 3 kinds of detailed execution modes below.
Execution mode one, with reference to Fig. 4, present embodiment is given in MISO(multiple input single output) implementation of secret communication method under system.Communication system is made up of transmit leg (Alice) and recipient (Bob).Alice configures N
troot dual-mode antenna, Bob sets single antenna, and therefore system can only realize single-stream transmission, the N of Alice configuration
tchannel between the single antenna that root dual-mode antenna and Bob set becomes equivalent spatial domain channel.Listener-in Eve can configure multiple antennas and intercept and capture performance to improve it.
1) the saltus step rule of Alice and Bob off-line arrangement spatial domain channel
now
in element be send the preliminary treatment weights of signal.According to hop rate r=N and the transmitting antenna number N of Γ setting
trandom generation matrix
singular value decomposition P=U ∑ V is carried out to it
h, wherein
and V
n × Nbe respectively the left and right singular matrix of P and there is characteristic at the tenth of the twelve Earthly Branches.Therefore each column vector of U and V all can alternatively preliminary treatment weights.In actual design, preliminary treatment weights only need keep statistical uncorrelation.
2) Alice sends pilot frequency sequence to Bob.At this, the process of pilot frequency sequence adopts the mode of orthogonal training.Alice applies different orthogonal spreading sequence codes to the pilot frequency sequence that every root antenna sends.Bob carries out channel estimating according to the pilot signal obtained, and estimates the channel gain coefficient between Alice in the n moment
bob can adjust channel estimating interval according to channel variance situation.
3) channel hopping times N can be obtained according to channel hopping Cahn-Ingold-Prelog sequence rule Γ for n moment modulation symbol x (n), Alice.In weights set
middle Stochastic choice N group preliminary treatment weights
formed
w (n) carries out preliminary treatment to transmission signal x (n), generates and sends signal S (n)=W (n) x (n), wherein N
tthe transmission signal of the corresponding time slice of each row of × N matrix S (n).In reality, h (n) w forms equivalent channel, different in each symbol
create N equivalent channel hopping.
4) Bob Received signal strength y in n moment mark space
h(n)=h (n) S (n)+v
h(n), wherein h (n) is the channel gain between Alice and Bob,
for the additive noise of different time fragment in mark space.Bob determines according to saltus step rule preconditioning matrix W (n) that n moment Alice adopts.Finally combine h (n), Bob to received signal y (n) carries out following decoding:
The process of Alice and Bob circulation execution step 2-4 carries out the safe transmission of subsequent brew symbol.
For Eve, Eve equally can Received signal strength Y ' (n)=H ' (n) S (n)+V ' (n), wherein H ' (n) is the channel gain matrix between Alice and Eve, and V ' (n) represents that additivity declines.But Eve does not share saltus step rule Ψ in advance, cannot obtain transition times N and preliminary treatment weighted vector.Equivalent channel saltus step makes the Received signal strength of Eve show as random fast change, is difficult to carry out correct demodulation to it.
Execution mode two: with reference to Fig. 5, present embodiment is given in the implementation under mimo system.Communication system is made up of transmit leg (Alice) and recipient (Bob).Alice configures N
troot dual-mode antenna, Bob configures N
rroot dual-mode antenna, therefore system can realize multiple stream transmission, the N of Alice configuration
troot dual-mode antenna, the N configured with Bob
requivalent spatial domain channel is formed between root dual-mode antenna.Listener-in Eve can configure multiple antennas and intercept and capture performance to improve it.
1) the saltus step rule of Alice and Bob off-line arrangement spatial domain channel
now
in element be send the preliminary treatment weights of signal.According to hop rate r=N and the transmitting antenna number N of Γ setting
trandom generation matrix
singular value decomposition P=U ∑ V is carried out to it
h, wherein
and V
n × Nbe respectively the left and right singular matrix of P and there is characteristic at the tenth of the twelve Earthly Branches.Therefore each column vector of U and V all can alternatively preliminary treatment weights.In actual design, preliminary treatment weights only need keep statistical uncorrelation.
2) Alice sends pilot frequency sequence to Bob.At this, the process of pilot frequency sequence adopts the mode of orthogonal training.Alice applies different orthogonal spreading sequence codes to the pilot frequency sequence that every root antenna sends.Bob obtains pilot signal, carries out channel estimating, and estimates the channel gain matrix between Alice in the n moment.Bob can adjust channel estimating interval according to channel variance situation.
3) for m data stream x (n) that the n moment is to be sent, Alice obtains equivalent channel transition times N in each modulation symbol according to channel hopping Cahn-Ingold-Prelog sequence rule Γ.In weights set
in be m data stream respectively Stochastic choice N group preliminary treatment weights
formed
wherein m × N
tmatrix
the preliminary treatment weight matrix of each channel hopping.
preliminary treatment is carried out to transmission signal x (n)
wherein N
tn × 1 vector S (n) is the row stack of N transmission signal.In reality
form equivalent channel, W different in each symbol
ncreate N equivalent channel hopping.
4) Bob Received signal strength Y in n moment mark space
h(n)=H (n) S (n)+V
h(n), wherein H (n) is the channel gain between Alice and Bob,
for the additive noise of different time fragment in mark space.Bob determines according to saltus step rule the preconditioning matrix that n moment Alice adopts
bob to received signal Y (n) carries out following maximum-likelihood decoding:
Wherein
for modulation symbol set.
The process of Alice and Bob circulation execution step 2-4 carries out the safe transmission of subsequent brew symbol.
For Eve, Eve equally can Received signal strength Y ' (n)=H ' (n) S (n)+V ' (n), wherein H ' (n) is the channel gain matrix between Alice and Eve, and V ' (n) represents that additivity declines.But Eve does not share saltus step rule Ψ in advance, cannot obtain the preliminary treatment weighted vector of transition times N and each data flow.Equivalent channel saltus step makes the Received signal strength of Eve show as random fast change, and any data flow is all difficult to obtain correct demodulation.
Execution mode three: this embodiment is given in MISO(multiple input single output) implementation under system.Spatial domain channel hopping is realized unlike Alice in this embodiment by switching different transmitting antennas in all antennas from embodiment one.Communication system is made up of transmit leg (Alice) and recipient (Bob), and Alice configures N
troot dual-mode antenna, Bob sets single antenna, and therefore system can only realize single-stream transmission.
1) the saltus step rule of Alice and Bob off-line agreement spatial domain channel
now the Ψ Alice be reduced to represented by Γ selects single antenna to send the antenna activation index sequence of signal, also can be that { the different antennae combination represented by 0,1} sends preliminary treatment weight w ∈.
2) Alice sends pilot frequency sequence to Bob.At this, the process of pilot frequency sequence adopts the mode of orthogonal training.Alice applies different orthogonal spreading sequence codes to the pilot frequency sequence that every root antenna sends.Bob obtains pilot signal, carries out channel estimating, and estimates the channel gain coefficient between Alice in the n moment
bob can adjust channel estimating interval according to channel variance situation.
3) for each modulation symbol x (n), Alice determines channel hopping times N, in set according to hopping sequence rule Γ
middle Stochastic choice N group preliminary treatment weighted vector
now
using 0 and 1 as element
pass through weighted vector
preliminary treatment is carried out to transmission signal
be equivalent to and have selected part transmitting antenna transmission x (n).The antenna of the positional representation Alice respective index at element 1 place is activated, on the contrary the unactivated state of remaining.The current antenna number in order to transmit x (n) by
the quantity of middle element 1 determines.Therefore, different
for x (n) defines different transmission channels.
4) Bob Received signal strength y in n moment mark space
h(n)=h (n) S (n)+v
h(n), wherein h (n) is the channel gain between Alice and Bob,
for the additive noise of different time fragment in mark space.Bob determines according to saltus step rule the transmitting antenna that n moment Alice selects.Finally combine h (n), Bob to received signal y (n) carries out merging reception.
The process of Alice and Bob circulation execution step 2-4 carries out the safe transmission of subsequent brew symbol.
For Eve, Eve equally can Received signal strength Y ' (n)=H ' (n) S (n)+V ' (n), wherein H ' (n) is the channel gain matrix between Alice and Eve, and V ' (n) represents that additivity declines.But Eve shares saltus step rule Ψ in advance, cannot obtain the transmitting antenna that the transition times N of each symbol and Alice uses at every turn.Thus and physical channel between Alice show as and become soon at random, be difficult to carry out correct demodulation to received signal.
The embodiment of the present invention utilizes abundant wireless spatial domain channel resource, secure communication of the present invention is realized by the quick switching of wireless spatial domain channel resource, adopt multi-antenna technology can bring diversity gain and spatial multiplexing gain at the situation down feed system not increasing spectral bandwidth simultaneously, also namely significantly improve reliability and the validity of system.
Be described the antenna equipment that the embodiment of the present invention provides below, the antenna equipment of following description is corresponding with the method that Fig. 1 describes, and both contents can cross-referenced correspondence.
The structured flowchart of the antenna equipment that Fig. 6 provides for the embodiment of the present invention, this antenna equipment is multi-antenna, and with reference to Fig. 6, this equipment can comprise:
Channel hopping number of times determination module 100, for according to the channel hopping speed in preset wireless channel saltus step rule, determines the channel hopping number of times of the modulation symbol of current time within the transmission cycle of this symbol;
Optionally, wireless channel saltus step rule install beforehand is in the memory cell of equipment.
Preliminary treatment weights choose module 110, for from the preliminary treatment weights set in preset wireless channel saltus step rule, choose the preliminary treatment weights of current time and the corresponding number of described channel hopping number of times;
Pretreatment module 120, for according to selected preliminary treatment weights, carries out preliminary treatment to described symbol to be modulated, generates and sends signal;
Sending module 130, for within the transmission cycle of described transmission signal, according to the channel hopping order in preset wireless channel saltus step rule, and the aerial information that described channel hopping is corresponding, in the process of transmitting sending signal, carry out the channel hopping with the corresponding number of times of described channel hopping number of times, complete the transmission sending signal.
Optionally, the set of preliminary treatment weights can comprise: the multiple random vector changing modulation symbol width/phase modulation intelligence, and/or, select the gating variable of transmitting antenna.
The structured flowchart of the sending module 130 that Fig. 7 provides for the embodiment of the present invention, with reference to Fig. 7, sending module 130 can comprise:
Division unit 131, for being the signal segment with the corresponding number of described channel hopping number of times by described transmission division of signal;
Allocation units 132, for the sequencing according to the channel hopping in preset wireless channel saltus step rule, are sequentially dispensed to antenna corresponding to each channel hopping by each signal segment;
Transmitting element 133, for sequentially sending each signal segment in each respective antenna, completes the transmission sending signal.
Optionally, equipment shown in Fig. 6 can also comprise:
Pilot frequency sequence sending module, for sending pilot frequency sequence to the recipient of described transmission signal, so that described recipient estimates the channel gain coefficient between the transmit leg of described transmission signal and recipient;
Extension process module, for when transmission receiving side signal is multi-antenna, carries out signal extension process to described modulation symbol, to transmit multi-stream information on multiple antennas simultaneously.
The another structured flowchart of the antenna equipment that Fig. 8 provides for the embodiment of the present invention, shown in Fig. 8, the description of method shown in equipment with Fig. 3 is corresponding, both content can cross-referenced correspondence, antenna equipment shown in Fig. 8 can be multi-antenna also can be single antenna device reference Fig. 8, and this antenna equipment can comprise:
Receiver module 200, for the transmission signal that Received signal strength transmit leg is sent by multiple antennas;
Send signaling channel transition times determination module 210, for according to the channel hopping speed in preset wireless channel saltus step rule, determine to send channel hopping number of times corresponding to signal;
Send Signal Pretreatment weights determination module 220, for according to the preliminary treatment weights set in preset wireless channel saltus step rule, and the channel hopping number of times of described correspondence, determine to send signal at preliminary treatment weights corresponding to delivery time;
Demodulation coding module 230, for carrying out demodulation coding according to determined preliminary treatment weights to described transmission signal, generates modulation symbol.
Optionally, equipment shown in Fig. 8 can also comprise: pilot frequency sequence receiver module, the pilot frequency sequence that the transmit leg for receiving described transmission signal sends, so that the channel gain coefficient between the transmit leg of estimation and described transmission signal.
The structured flowchart of the secret signalling that Fig. 9 provides for the embodiment of the present invention, with reference to Fig. 9, this system can comprise: the first antenna equipment 1 and the second antenna equipment 2, and wherein, the first antenna equipment 1 can as shown in Figure 6, and the second antenna equipment 2 can be as shown in Figure 8.
In this specification, each embodiment adopts the mode of going forward one by one to describe, and what each embodiment stressed is the difference with other embodiments, between each embodiment identical similar portion mutually see.For device disclosed in embodiment, because it corresponds to the method disclosed in Example, so description is fairly simple, relevant part illustrates see method part.
Professional can also recognize further, in conjunction with unit and the algorithm steps of each example of embodiment disclosed herein description, can realize with electronic hardware, computer software or the combination of the two, in order to the interchangeability of hardware and software is clearly described, generally describe composition and the step of each example in the above description according to function.These functions perform with hardware or software mode actually, depend on application-specific and the design constraint of technical scheme.Professional and technical personnel can use distinct methods to realize described function to each specifically should being used for, but this realization should not thought and exceeds scope of the present invention.
The software module that the method described in conjunction with embodiment disclosed herein or the step of algorithm can directly use hardware, processor to perform, or the combination of the two is implemented.Software module can be placed in the storage medium of other form any known in random asccess memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable ROM, register, hard disk, moveable magnetic disc, CD-ROM or technical field.
To the above-mentioned explanation of the disclosed embodiments, professional and technical personnel in the field are realized or uses the present invention.To be apparent for those skilled in the art to the multiple amendment of these embodiments, General Principle as defined herein can without departing from the spirit or scope of the present invention, realize in other embodiments.Therefore, the present invention can not be restricted to these embodiments shown in this article, but will meet the widest scope consistent with principle disclosed herein and features of novelty.
Claims (9)
1. a secret communication method, is characterized in that, is applied to multi-antenna, and described method comprises:
According to the channel hopping speed in preset wireless channel saltus step rule, determine the channel hopping number of times of the modulation symbol of current time within the transmission cycle of this symbol; Wherein, described wireless channel saltus step rule represents with Ψ,
for the preliminary treatment weights set of modulation symbol, Γ is hopping sequence rule,
be made up of pseudo random sequence with Γ, described hopping sequence rule Γ arranges the hop rate of spatial domain channel simultaneously, first determine the current time that modulation symbol sends, thus determine the hop rate r=1/t of the spatial domain channel of current time by the hopping sequence rule Γ of described current time
c, wherein t
cfor the time of a certain selected preliminary treatment weights continuous action, namely signal is in the duration of channel corresponding to these preliminary treatment weights, and the transmitting time cycle of described modulation symbol is T
s, described T
sunit be second, in each modulation symbol interval, spatial domain channel hopping number of times is N=T
s/ t
c;
From in the preliminary treatment weights set preset wireless channel saltus step rule, choose the preliminary treatment weights of current time and the corresponding number of described channel hopping number of times; Wherein, the multiple random vector of the described preliminary treatment weights for a change width/phase modulation intelligence of modulation symbol, or, change the multiple random vector of the width/phase modulation intelligence of modulation symbol and select the gating variable of transmitting antenna;
According to selected preliminary treatment weights, preliminary treatment is carried out to described modulation symbol, generate and send signal;
The obtain manner of described multiple random vector is: according to the hop rate r of hopping sequence rule Γ setting, if r=N, and the number N of transmitting antenna
t, random generation matrix P, carries out singular value decomposition P=U ∑ V to this matrix
h, wherein
and V
n × Nbe respectively the left and right singular matrix of P and there is characteristic at the tenth of the twelve Earthly Branches, described in
and V
n × Neach column vector all can be used as candidate's preliminary treatment weights;
Within the transmission cycle of described transmission signal, according to the channel hopping order in preset wireless channel saltus step rule, and the aerial information that described channel hopping is corresponding, in the process of transmitting sending signal, carry out the channel hopping with the corresponding number of times of described channel hopping number of times, complete the transmission sending signal.
2. method according to claim 1, it is characterized in that, described according to the channel hopping order in preset wireless channel saltus step rule, and the aerial information that described channel hopping is corresponding, in the process of transmitting sending signal, carry out comprising with the process of the channel hopping of the corresponding number of times of described channel hopping number of times:
Be the signal segment with the corresponding number of described channel hopping number of times by described transmission division of signal, according to the sequencing of the channel hopping in preset wireless channel saltus step rule, each signal segment is sequentially dispensed to antenna corresponding to each channel hopping, each respective antenna sequentially sends each signal segment, completes the transmission sending signal.
3. method according to claim 1, is characterized in that, also comprises: the recipient to described transmission signal sends pilot frequency sequence, so that described recipient estimates the channel gain coefficient between the transmit leg of described transmission signal and recipient;
When transmission receiving side signal is multi-antenna, also comprise: signal extension process is carried out to described modulation symbol, to transmit multi-stream information on multiple antennas simultaneously.
4. a secret communication method, is characterized in that, comprising:
The transmission signal that Received signal strength transmit leg is sent by multiple antennas; Wherein, the transmission signal received is Y (n)=H (n) S (n)+V (n), the wherein transmission signal that generates after preliminary treatment for modulation symbol of S (n), H (n) is road gain matrix, the additive noise that in the mark space that V (n) is signal delivery time n, different time fragment Received signal strength suffers;
According to the channel hopping speed in preset wireless channel saltus step rule, determine to send channel hopping number of times corresponding to signal; Wherein, described wireless channel saltus step rule is made an appointment by signalling and receiving side signal, and described wireless channel saltus step rule represents with Ψ,
for the set of modulation symbol preliminary treatment weights, Γ is hopping sequence rule,
be made up of pseudo random sequence with Γ, described hopping sequence rule Γ has arranged the hop rate r=1/t of spatial domain channel simultaneously
c, described channel hopping times N=T
s/ t
c;
According to the preliminary treatment weights set in preset wireless channel saltus step rule, and the channel hopping number of times that described transmission signal is corresponding, determine to send signal at preliminary treatment weights corresponding to delivery time; Wherein, the multiple random vector of the described preliminary treatment weights for a change width/phase modulation intelligence of modulation symbol, or, change the multiple random vector of the width/phase modulation intelligence of modulation symbol and select the gating variable of transmitting antenna;
The obtain manner of described multiple random vector is: according to the hop rate r of hopping sequence rule Γ setting, if r=N, and the number N of transmitting antenna
t, random generation matrix P, carries out singular value decomposition P=U ∑ V to this matrix
h, wherein
and V
n × Nbe respectively the left and right singular matrix of P and there is characteristic at the tenth of the twelve Earthly Branches, described in
and V
n × Neach column vector all can be used as candidate's preliminary treatment weights;
According to determined preliminary treatment weights, demodulation coding is carried out to described transmission signal, generate modulation symbol.
5. method according to claim 4, is characterized in that, also comprises:
The pilot frequency sequence that the transmit leg receiving described transmission signal sends, so that the channel gain coefficient between the transmit leg of estimation and described transmission signal.
6. an antenna equipment, is characterized in that, described antenna equipment is multi-antenna, comprising:
Channel hopping number of times determination module, for according to the channel hopping speed in preset wireless channel saltus step rule, determines the channel hopping number of times of the modulation symbol of current time within the transmission cycle of this symbol; Wherein, described wireless channel saltus step rule represents with Ψ,
for the preliminary treatment weights set of modulation symbol, Γ is hopping sequence rule,
be made up of pseudo random sequence with Γ, described hopping sequence rule Γ arranges the hop rate of spatial domain channel simultaneously, first determine the current time that modulation symbol sends, thus determine the hop rate r=1/t of the spatial domain channel of current time by the hopping sequence rule Γ of described current time
c, wherein t
cfor the time of a certain selected preliminary treatment weights continuous action, namely signal is in the duration of channel corresponding to these preliminary treatment weights, and the transmitting time cycle of described modulation symbol is T
s, described T
sunit be second, in each modulation symbol interval, spatial domain channel hopping number of times is N=T
s/ t
c;
Preliminary treatment weights choose module, for from the preliminary treatment weights set in preset wireless channel saltus step rule, choose the preliminary treatment weights of current time and the corresponding number of described channel hopping number of times; Wherein, the multiple random vector of the described preliminary treatment weights for a change width/phase modulation intelligence of modulation symbol, or, change the multiple random vector of the width/phase modulation intelligence of modulation symbol and select the gating variable of transmitting antenna; The obtain manner of described multiple random vector is: according to the hop rate r of hopping sequence rule Γ setting, if r=N, and the number N of transmitting antenna
t, random generation matrix P, carries out singular value decomposition P=U ∑ V to this matrix
h, wherein
and V
n × Nbe respectively the left and right singular matrix of P and there is characteristic at the tenth of the twelve Earthly Branches, described in
and V
n × Neach column vector all can be used as candidate's preliminary treatment weights;
Pretreatment module, for according to selected preliminary treatment weights, treats modulation symbol and carries out preliminary treatment,
s (n)=W (n) x (n);
Sending module, for within the transmission cycle of described transmission signal, according to the channel hopping order in preset wireless channel saltus step rule, and the aerial information that described channel hopping is corresponding, in the process of transmitting sending signal, carry out the channel hopping with the corresponding number of times of described channel hopping number of times, complete the transmission sending signal.
7. equipment according to claim 6, is characterized in that, described sending module comprises:
Division unit, for being the signal segment with the corresponding number of described channel hopping number of times by described transmission division of signal;
Allocation units, for the sequencing according to the channel hopping in preset wireless channel saltus step rule, are sequentially dispensed to antenna corresponding to each channel hopping by each signal segment;
Transmitting element, for sequentially sending each signal segment in each respective antenna, completes the transmission sending signal.
8. the equipment according to claim 6 or 7, is characterized in that, described equipment also comprises:
Pilot frequency sequence sending module, for sending pilot frequency sequence to the recipient of described transmission signal, so that described recipient estimates the channel gain coefficient between the transmit leg of described transmission signal and recipient;
Extension process module, for when transmission receiving side signal is multi-antenna, carries out signal extension process to described modulation symbol, to transmit multi-stream information on multiple antennas simultaneously.
9. an antenna equipment, is characterized in that, comprising:
Receiver module, for the transmission signal that Received signal strength transmit leg is sent by multiple antennas;
Send signaling channel transition times determination module, for according to the channel hopping speed in preset wireless channel saltus step rule, determine to send channel hopping number of times corresponding to signal; Wherein, described wireless channel saltus step rule is made an appointment by signalling and receiving side signal, and described wireless channel saltus step rule represents with Ψ,
for the set of modulation symbol preliminary treatment weights, Γ is hopping sequence rule,
be made up of pseudo random sequence with Γ, described hopping sequence rule Γ has arranged the hop rate r=1/t of spatial domain channel simultaneously
c, described channel hopping times N=T
s/ t
c;
Send Signal Pretreatment weights determination module, for according to the preliminary treatment weights set in preset wireless channel saltus step rule, and the channel hopping number of times that described transmission signal is corresponding, determine to send signal at preliminary treatment weights corresponding to delivery time; Wherein, the multiple random vector of the described preliminary treatment weights for a change width/phase modulation intelligence of modulation symbol, or, change the multiple random vector of the width/phase modulation intelligence of modulation symbol and select the gating variable of transmitting antenna;
The obtain manner of described multiple random vector is: according to the hop rate r of hopping sequence rule Γ setting, if r=N, and the number N of transmitting antenna
t, random generation matrix P, carries out singular value decomposition P=U ∑ V to this matrix
h, wherein
and V
n × Nbe respectively the left and right singular matrix of P and there is characteristic at the tenth of the twelve Earthly Branches, described in
and V
n × Neach column vector all can be used as candidate's preliminary treatment weights;
Demodulation coding module, for carrying out demodulation coding according to determined preliminary treatment weights to described transmission signal, generates modulation symbol.
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| CN103199909B (en) * | 2013-04-16 | 2016-04-06 | 中国人民解放军信息工程大学 | Realize the signal sending, receiving method of secure communication, device and communication system |
| CN104168622B (en) * | 2014-09-01 | 2018-03-20 | 西安电子科技大学 | Distributed multichannel handshake method based on channel hopping |
| CN105636025A (en) * | 2015-07-08 | 2016-06-01 | 宇龙计算机通信科技(深圳)有限公司 | Secure data transmission method and system |
| CN105245520B (en) * | 2015-10-12 | 2018-03-30 | 中国人民解放军信息工程大学 | A kind of active defense method for the eavesdropping of telecommunications speech communication |
| CN107147486A (en) * | 2017-05-10 | 2017-09-08 | 成都课迪科技有限公司 | A kind of platform data encryption method and device based on dynamic variable length code |
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