CN109510705A - Based on the preprocess method for extracting active path in key generation system - Google Patents
Based on the preprocess method for extracting active path in key generation system Download PDFInfo
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- CN109510705A CN109510705A CN201811590795.0A CN201811590795A CN109510705A CN 109510705 A CN109510705 A CN 109510705A CN 201811590795 A CN201811590795 A CN 201811590795A CN 109510705 A CN109510705 A CN 109510705A
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- active path
- time domain
- threshold value
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
- H04L9/08—Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords
- H04L9/0861—Generation of secret information including derivation or calculation of cryptographic keys or passwords
- H04L9/0875—Generation of secret information including derivation or calculation of cryptographic keys or passwords based on channel impulse response [CIR]
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
- H04L9/08—Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords
- H04L9/0816—Key establishment, i.e. cryptographic processes or cryptographic protocols whereby a shared secret becomes available to two or more parties, for subsequent use
- H04L9/0838—Key agreement, i.e. key establishment technique in which a shared key is derived by parties as a function of information contributed by, or associated with, each of these
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- Engineering & Computer Science (AREA)
- Computer Security & Cryptography (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Noise Elimination (AREA)
Abstract
The invention belongs to Communication Anti-Jamming Techniques field, particularly relate in key generation system based on the preprocess method for extracting active path.The present invention is proposed for the inconsistent higher problem of rate initial in key generation system based on the channel estimation value pretreating scheme for extracting active path, the stronger propagation path of power and other less power paths in time domain are filtered off in the time domain by extracting signal, to effectively antagonize the interference of noise suffered in communication process and the influence of multipath effect, the inconsistent rate of initial key is reduced.
Description
Technical field
The invention belongs to Communication Anti-Jamming Techniques field, particularly relate to effective based on extracting in key generation system
The preprocess method in path.
Background technique
In the key generation system based on the characteristic of channel, the reciprocity in short-term of channel is that legitimate receipt both sides establish unanimously
The basis of property shared key.But due to wireless communication in transmission channel complexity, emit signal during propagation with ground
Scattered wave caused by the back wave in face and various barriers is superimposed, to produce shade, multipath effect, brings difference
Decline and extension.Along with the influence of noise suffered in communication process, the signal for causing legitimate correspondence both sides to receive is deposited
In certain deviation, it is its subsequent key agreement mistake that cause both sides' initial key, there is certain inconsistent rates
Journey brings very big difficulty.Therefore, the shadow of multipath, shade and other interference how is overcome by certain pretreating scheme
It rings, reduces the inconsistent rate of initial key of legitimate receipt both sides, become the key studied in the field of key generation in recent years.
Signal denoising is the key technology in field of signal processing.In previous research, conventional Fourier transform by when
Domain signals and associated noises are mapped to frequency domain and are filtered, and have significant gain for the denoising of stationary signal.But after its transformation
Signal lack the measurement in time domain to be difficult to investigate original signal in different time points on spectral characteristic, therefore be not suitable for
Non-stationary signal.Wavelet transformation has preferable fitting effect, quilt to sophisticated signal due to the local expansion performance of its basic function
It is widely used in the denoising of non-stationary signal, but there are certain contingency and subjectivity, certain journeys for the selection of wavelet basis function
The fitting effect of original signal is affected on degree.
Summary of the invention
Since the final purpose of key generation system is so that legitimate receipt both sides generate consistent key sequence, and are not concerned with
The integrality of original channel information and whether can receiving end reconstruct transmitting signal, be based on this, the present invention for key give birth to
It proposes at the inconsistent higher problem of rate initial in system based on the channel estimation value pretreating scheme for extracting active path, leads to
It crosses extraction signal and the stronger propagation path of power and filters off other less power paths in time domain in the time domain, thus effectively right
The interference of suffered noise and the influence of multipath effect, reduce the inconsistent rate of initial key in anti-communication process.
In order to make it easy to understand, key generation system is introduced first:
Mainly enhance several steps comprising channel detection, quantization, key agreement, secrecy in traditional secrete key generation system.?
During channel detection, Alice, Bob send mutually training sequence, in advance carry out signal to be sent in transmitting terminal orthogonal
Frequency division multiplexing (Orthogonal Frequency Division Multiplexing, OFDM) modulation, and in OFDM symbol
Pilot frequency sequence is placed according to blocky, in receiving end with least square (Least Squares, LS) algorithm to the letter received
Breath sequence carries out channel estimation and obtains channel measured value, and from the characteristic parameter wherein extracted for key generation, the present invention
The characteristic parameter generated using the range value of channel response as subsequent key.
In quantization step, legitimate receipt both sides scheme that the channel characteristics measured value extracted is general with section etc. respectively
It determines quantization threshold, the binary bits after quantization is determined according to section serial number where channel characteristics measured value.The step is realized
Be analog signal digital function.The obtained binary sequence of legitimate receipt both sides is referred to as initial key after quantization
Sequence, inconsistent rate (Key Disagreement Rate, KDR) is defined as:
It therefore, is subsequent close within the acceptable range by the inconsistent rate control of key by certain pretreating scheme
The key of key negotiation step success.
The multipath channel time domain impulse response and channel frequency domain response of ofdm system are the relationships of Fourier transform pair, because
This, the channel measured value that legitimate receipt side is obtained by LS channel estimationCarrying out N point IDFT transformation, (N is ofdm system
The number of sub-carriers), the estimation of multipath channel time domain impulse response can be obtained
Ideal multipath channel only can have impulse response at the sampled point of corresponding time delay, and on remaining sampling point position
Impulse response is 0.And in practical communication scene, it is converted by IDFTIt adopts channel multi-path time delay is corresponding
Sampling point position has apparent impulse, and the impulse amplitude on several paths successively reduces；But it is general on other time-domain positions
There is no neutral element, this is because the influence of noise and interference is so that there is certain to rise the position between multipath impact
Volt.When noise component(s) is sufficiently strong, the faint propagation path of fraction of signal strength by noise signal it could even be possible to flooded, hardly possible
To differentiate.
It is right in the present invention based on thisCertain processing is carried out, i.e. the extraction stronger propagation path of signal power, retained
Impulse responses in corresponding delay positions, and by the component zero setting in other positions, with filter off partial noise component and its
His less power diameter.Its specific implementation method are as follows:
A. the threshold value of screening active path is determined.The setting of the threshold value can dynamically be adjusted according to actual channel situation
It is whole.
B. according to the threshold value determined, by multipath time domain impulse responseIt is screened, forIn be greater than threshold value
Component retained, while filter off wherein be less than threshold value component.
Significantly, since the difference of practical communication environment, each diameter time delay of multipath channel is often not necessarily pumping
The integral multiple of sample time, and since the influence of noise can influence the accuracy of threshold value judgement to a certain extent, it is based on this, is being extracted
When active path, usually retain several sampled points around the path for being more than threshold value simultaneously.
The estimation of the multipath channel time domain impulse response after denoising is obtained by extracting active pathBy by its
It carries out N point DFT processing and transforms to frequency domain, channel frequency response estimated value can be retrievedAs by the pre- place of denoising
The channel measured value obtained after reason.
Beneficial effects of the present invention are that the frequency domain response that this programme obtains channel estimation transforms to time domain, and is extracting
Noise component(s) and other less power diameters are filtered off together while signal power stronger path.It is shown through emulation, we
Case is effective against the interference of noise suffered in communication process and the influence of multipath effect, so that it is double to reduce legitimate receipt
The inconsistent rate of initial key of side.
Detailed description of the invention
Fig. 1 is system block diagram of the invention；
Fig. 2 is multipath channel time domain impulse response schematic diagram；
Fig. 3 is that the inconsistent rate performance of initial key compares in key generation system.
Specific embodiment
In Summary to the present invention have been described in detail, this is further illustrated below with reference to simulated example
The practicability of invention.
Specific embodiments of the present invention are consistent in order to obtain as shown in Figure 1, Alice and Bob are legitimate correspondence both sides
Key passes sequentially through channel detection, wavelet transformation pretreatment, quantifies several steps and obtain initial key.
Specific implementation step approximately as:
Step 1:Alice and Bob sends mutually detection sequence in the channel detection stage；
Step 2: signal being subjected to N point IDFT transformation in receiving end, obtains the estimation of multipath channel time domain impulse response
Step 3: extracting time domain impulse response estimation valueIn active path, it is specific as follows:
A. the threshold value of screening active path is determined.The setting of the threshold value can dynamically be adjusted according to actual channel situation
It is whole.
It b., will be by multipath time domain impulse response according to the threshold value determinedIt is screened, forIn be greater than threshold
The component of value is retained, and filters off the component for being wherein less than threshold value.
Step 4: obtaining the estimation of the multipath channel time domain impulse response after denoising by extracting active pathIt is logical
Cross carried out N point DFT processing transform to frequency domain, channel frequency response estimated value can be retrievedAs through the past
It makes an uproar obtained channel measured value after pretreatment.
Step 5: in obtained channel frequency response estimationMiddle extraction channel characteristics, and by the channel characteristics extracted into
The general quantization such as row, obtains initial key, and the inconsistent rate of the initial key for calculating legitimate receipt both sides.
Table 1 illustrates the parameter setting in emulation.Rayleigh multipath channel is used in emulation, extracts the width of channel response
Degree is used as channel characteristics measured value, and using the general quantization such as 3 bit sections.Table 2 illustrates each diameter for emulating multipath channel used
Power time delay distribution table.
The setting of 1 simulation parameter of table
2 COST207 of table, six diameter channel power delay distribution table
Fig. 2 illustrates the time domain impulse response schematic diagram of multipath channel.As shown, due to the influence of noise, the 6th diameter
Channel Impulse is flooded by noise substantially, if the component is retained, the channel measured value that legitimate correspondence both sides receive
It will largely be influenced by noise, to cause higher inconsistent rate.Based on this, the channel is only extracted in this programme
Former propagation paths carry out performance comparison.
Fig. 3 illustrates variation feelings when increasing by the initial inconsistent rate of the present invention program before and after the processing with signal-to-noise ratio
Condition.Simulation result shows, proposed in the present invention based on drop of the pretreating scheme to initial inconsistent rate for extracting active path
It is low play the role of it is more significant, and extract active path number it is fewer, performance gain is about obvious.This is because a plurality of retaining
Also the noise on corresponding time domain point is remained while propagation path, and the presence meeting of noise is so that legitimate correspondence both sides receive
Channel characteristics measured value have certain deviation, to cause the inconsistent rate of certain initial key.It is since key generates
The final purpose of system be so that legitimate receipt both sides generate consistent key sequence, and and be not concerned with the integrality of original channel information
And whether can receiving end reconstruct transmitting signal, be based on this, only extract multipath channel first strongest diameter of power and
Filter off the performance that other components can be optimal.
Claims (1)
1. the key generation system successively includes channel based on the preprocess method for extracting active path in key generation system
Detection, quantization, key agreement and secrecy enhance several steps；It is characterized in that, further including mentioning between channel detection and quantization
The step of taking active path, specifically, after channel detection step obtains channel estimation value:
Signal is subjected to N point IDFT transformation in receiving end, obtains the estimation of multipath channel time domain impulse response
Extract time domain impulse response estimation valueIn active path, it is specific as follows:
A. the threshold value of screening active path is determined, the setting of the threshold value is dynamically adjusted according to actual channel situation；
B. according to the threshold value determined, to multipath time domain impulse responseIt is screened, forIn be greater than threshold value component
Retained, and filters off the component for being wherein less than threshold value；
The estimation of the multipath channel time domain impulse response after denoising is obtained by extracting active pathBy carried out
N point DFT processing transforms to frequency domain, can retrieve channel frequency response estimated value As after noise suppression preprocessing
Obtained channel measured value.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101267422A (en) * | 2008-03-10 | 2008-09-17 | 电子科技大学 | A frequency domain channel estimation method for OFDM multiplex system |
| US20160337122A1 (en) * | 2015-05-11 | 2016-11-17 | Electronics And Telecommunications Research Institute | Method and apparatus for generating secret key in wireless communication network |
| CN108718234A (en) * | 2018-05-04 | 2018-10-30 | 南京邮电大学 | Wirelessly communicate the key generation method based on adjustable angle phase protection band |
-
2018
- 2018-12-25 CN CN201811590795.0A patent/CN109510705A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101267422A (en) * | 2008-03-10 | 2008-09-17 | 电子科技大学 | A frequency domain channel estimation method for OFDM multiplex system |
| US20160337122A1 (en) * | 2015-05-11 | 2016-11-17 | Electronics And Telecommunications Research Institute | Method and apparatus for generating secret key in wireless communication network |
| CN108718234A (en) * | 2018-05-04 | 2018-10-30 | 南京邮电大学 | Wirelessly communicate the key generation method based on adjustable angle phase protection band |
Non-Patent Citations (5)
| Title |
|---|
| KAN ZHENG ET AL.: "《DFT-Based Channel Estimation in Comb-Type Pilot-Aided OFDM Systems with Virtual Carriers》", 《2007 IEEE 18TH INTERNATIONAL SYMPOSIUM ON PERSONAL,INDOOR AND MOBILE RADIO COMMUNICATIONS》 * |
| YUQIN GAN ET AL.: "《Improved Channel Information Extraction toward Efficient Secret Key Generation》", 《2019 19TH IEEE INTERNATIONAL CONFERENCE ON COMMUNICATION TECHNOLOGY》 * |
| 侯焕鹏: "《基于星地信道特性的物理层安全关键技术研究及实现》", 《中国优秀硕士学位论文全文数据库 信息科技辑》 * |
| 李古月等: "《无线信道的密钥生成方法》", 《密码学报》 * |
| 甘雨沁: "《基于星地信道特性的物理层安全关键技术研究》", 《中国优秀硕士学位论文全文数据库 信息科技辑》 * |
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Application publication date: 20190322 |