CN113055154B - Repeatable chaos spread spectrum DCSK modulation and demodulation method and modem - Google Patents
Repeatable chaos spread spectrum DCSK modulation and demodulation method and modem Download PDFInfo
- Publication number
- CN113055154B CN113055154B CN202110323912.2A CN202110323912A CN113055154B CN 113055154 B CN113055154 B CN 113055154B CN 202110323912 A CN202110323912 A CN 202110323912A CN 113055154 B CN113055154 B CN 113055154B
- Authority
- CN
- China
- Prior art keywords
- signal
- dcsk
- chaotic
- rcss
- parallel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 41
- 238000001228 spectrum Methods 0.000 title claims abstract description 33
- 230000000739 chaotic effect Effects 0.000 claims abstract description 91
- 238000006243 chemical reaction Methods 0.000 claims abstract description 23
- 230000005540 biological transmission Effects 0.000 claims abstract description 10
- 108010076504 Protein Sorting Signals Proteins 0.000 claims description 40
- 238000005070 sampling Methods 0.000 claims description 20
- 230000003111 delayed effect Effects 0.000 claims description 11
- 230000000875 corresponding effect Effects 0.000 claims description 8
- 230000002596 correlated effect Effects 0.000 claims description 7
- 238000012545 processing Methods 0.000 claims description 5
- 230000001934 delay Effects 0.000 claims description 3
- 238000004891 communication Methods 0.000 abstract description 6
- 108010003272 Hyaluronate lyase Proteins 0.000 abstract description 4
- 230000008569 process Effects 0.000 description 5
- 239000000654 additive Substances 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000005094 computer simulation Methods 0.000 description 1
- 238000010219 correlation analysis Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000005562 fading Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000007430 reference method Methods 0.000 description 1
- 230000003252 repetitive effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000007480 spreading Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
Images
Classifications
-
- 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
- H04L9/001—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols using chaotic signals
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/69—Spread spectrum techniques
- H04B1/707—Spread spectrum techniques using direct sequence modulation
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/001—Modulated-carrier systems using chaotic signals
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L2209/00—Additional information or applications relating to cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00
- H04L2209/12—Details relating to cryptographic hardware or logic circuitry
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Computer Security & Cryptography (AREA)
- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
Abstract
The repeatable chaotic spread spectrum DCSK modulation and demodulation method is characterized in that a repeated chaotic spread spectrum sequence is generated by copying a reference signal of a differential chaotic shift keying modulation signal, the repeated chaotic spread spectrum sequence is multiplied by part of data streams after serial-parallel conversion to form an RCSS-DCSK signal, the other parallel data streams are subjected to DCSK modulation to form a DCSK signal, the RCSS-DCSK signal and the DCSK signal are added and then sent to a channel for transmission, and finally relevant demodulation is carried out at a receiving end to recover original information. The system adopting the modulation and demodulation method has the advantages that the error rate is lower than that of DCSK, CDSK and CD-DCSK systems under the condition of the same spreading factor, the smaller the spreading factor is, the lower the error rate is, the higher the confidentiality of the system is, an eavesdropper is more difficult to detect and recover original data, and the confidentiality requirement of the chaotic communication system in actual application can be better met.
Description
Technical Field
The invention relates to the technical field of communication signal processing, in particular to a repeatable chaotic spread spectrum DCSK modulation and demodulation method and a modem.
Background
The chaotic digital modulation technology not only can keep the characteristics of low interception probability, multipath effect reduction and the like of the traditional spread spectrum communication system, but also has unique advantages in many other aspects, such as reducing the hardware cost of the system, improving the communication safety, improving the performance of the spread spectrum communication system and the like. In recent years, the chaotic digital modulation technology has become one of the hot issues of concern and research in the nonlinear science and information science community.
Because a reliable and effective method is lacked at present to realize chaotic synchronization at a receiving end, most of the existing chaotic digital modulation and demodulation methods are also based on a transmission reference method, namely, a carrier signal and a signal carrying information are both sent to the receiving end. The Differential Chaos Shift Keying (DCSK) modulation and demodulation method does not need to complete channel estimation, can obtain relatively good error code performance, and shows strong competitiveness in many practical application occasions (such as wireless personal area networks, wireless sensor networks, and the like). However, the error rate still needs to be further improved, and in addition, the existing DCSK modulation and demodulation method has low confidentiality, and a transmission signal can be easily extracted through attack methods such as correlation analysis and the like after being intercepted.
Disclosure of Invention
One of the purposes of the present invention is to provide a repeatable chaotic spread spectrum DCSK modulation and demodulation method to solve the problem of low security of the existing DCSK modulation and demodulation method.
In order to achieve the purpose, the invention adopts the following technical scheme: a repeatable chaos spread spectrum DCSK modulation and demodulation method, at a sending end, a signal modulation process comprises the following steps:
1) performing serial-to-parallel conversion on an input serial information signal;
2) acquiring a discrete chaotic signal sequence and delaying the discrete chaotic signal sequence to obtain a DCSK reference signal; generating a repeatable chaotic spread spectrum sequence by using the discrete chaotic signal sequences before and after time delay to obtain an RCSS reference signal;
3) dividing the information signal after serial-parallel conversion into two parallel signals; one path of parallel signals is modulated with a DCSK reference signal through a discrete chaotic signal sequence to form a DCSK signal; the other path of parallel signals is modulated through an RCSS reference signal to form an RCSS-DCSK signal; and combining the DCSK signal with the RCSS-DCSK signal and sending the combined signal to a channel for transmission.
Further, at the receiving end, the signal demodulation process includes the following steps:
4) respectively carrying out relevant demodulation on the received DCSK signal and the RCSS-DCSK signal, and outputting corresponding demodulation data through threshold judgment;
5) and converting the obtained demodulation data into a path of serial demodulation data in parallel and serial mode and outputting the demodulated data.
Specifically, in step 1), serial information input in the current symbol period is serial-to-parallel converted.
In the step 2), a discrete chaotic signal sequence is generated by the chaotic signal generator, and then the discrete chaotic signal sequence generated by the chaotic signal generator is obtained.
Further, in step 3):
when one of the parallel signals is modulated through the discrete chaotic signal sequence and the DCSK reference signal, multiplying the DCSK reference signal in the current symbol period by the corresponding parallel signal to obtain a DCSK information signal, and modulating the DCSK information signal through the discrete chaotic signal sequence to form a DCSK signal;
when the RCSS reference signal is used for modulating the other path of parallel signal, the RCSS reference signal is multiplied by the corresponding parallel signal to obtain an RCSS-DCSK signal;
and when the other parallel signal is modulated by the RCSS signal, the RCSS signal is multiplied by the corresponding parallel signal.
And when the DCSK signal and the RCSS-DCSK signal are combined, the DCSK signal and the RCSS-DCSK signal are added.
Wherein, in step 4):
when carrying out correlation demodulation on the DCSK signal, delaying the received DCSK signal, multiplying the delayed DCSK signal by the undelayed DCSK signal, carrying out correlation processing, carrying out time domain sampling on the correlated signal, comparing a sampling value with a threshold value, and outputting demodulation data according to threshold judgment;
when the RCSS-DCSK signal is subjected to correlation demodulation, the received RCSS-DCSK signal and the DCSK signal which is not delayed are multiplied, then correlation processing is carried out, time domain sampling is carried out on the correlated signal, then the sampling value is compared with a threshold value, and demodulation data are output according to threshold decision.
In addition, the invention also relates to a repeatable chaotic spread spectrum DCSK modem, which comprises a modulator and a demodulator, wherein the modulator modulates the input serial information signal according to the methods of the steps 1) to 3).
Further, the demodulator demodulates the received signal according to the method of the above steps 4) to 5).
Specifically, the modulator comprises a chaotic signal generator, a delayer 1, a serial-parallel conversion circuit, a multiplier 1, a multiplier 2 and an adder;
the chaotic signal generator is used for generating a discrete chaotic signal sequence, the discrete chaotic signal sequence is delayed by the delayer 1 to obtain a DCSK reference signal in the current symbol period, and then the discrete chaotic signal sequence before and after delay is utilized to generate an RCSS reference signal; the serial-parallel conversion circuit converts serial information signals to be transmitted in the current symbol period into two parallel signals; the multiplier 1 multiplies a DCSK reference signal in a current symbol period by one of the parallel signals; the multiplier 2 multiplies the RCSS reference signal by another parallel signal; and the adder adds the DCSK signal and the RCSS-DCSK signal and then sends the added signals to a channel for transmission.
The demodulator comprises a delayer 2, a multiplier 3, a multiplier 4, a summator 1, a summator 2, a sampling switch, a decision device and a parallel-serial conversion circuit;
the delayer delays the received DCSK signal; the multiplier 3 multiplies the delayed DCSK signal by the undelayed DCSK signal; the multiplier 4 multiplies the RCSS-DCSK signal by the DCSK signal without time delay; the summer 1 is a correlation of the DCSK signal; the summer 2 is the correlation of the RCSS-DCSK signal; the sampling switch respectively carries out time domain sampling on the correlated signals; the decision device compares the sampling value with a threshold value and outputs a demodulation data bit according to threshold decision; and the parallel-serial conversion circuit converts the two obtained paths of demodulation data into one path of serial demodulation data in parallel-serial mode and outputs the demodulated data.
The invention adopts a repeatable Chaotic spread spectrum (DCSK) modulation and demodulation method which generates a repetitive Chaotic spread spectrum Sequence (RCSS) by copying a reference signal (DCSK) of a Differential Chaotic Keying modulation signal, multiplies the RCSS with a part of data streams after serial-parallel conversion, modulates the rest of parallel data streams according to the DCSK, adds the two parts of signals and then sends the signals to a channel for transmission, and performs related demodulation at a receiving end to recover original information. Under a multipath fading channel, the error rate of the system (RCSS-DCSK system) under the condition of the same spreading factor is lower than that of DCSK, CDSK and CD-DCSK systems, the smaller the spreading factor is, the lower the error rate is, in addition, the error rate of the RCSS-DCSK system when the noise which obeys Gaussian distribution is superposed in the channel is also lower than that of the system when the noise which obeys Rayleigh distribution is superposed, and particularly, the invention utilizes the discrete chaotic signal sequence before and after delay to generate the repeatable chaotic spreading sequence to obtain the RCSS reference signal, and modulates the data stream by the RCSS reference signal, so that the confidentiality of the DCSK system can be improved, an eavesdropper is more difficult to detect and recover the original data, and the confidentiality requirement of the chaotic communication system in actual application is better met.
Drawings
Fig. 1 is a schematic flow chart of an RCSS-DCSK modulation and demodulation method in an embodiment.
Fig. 2 is a schematic structural diagram of an RCSS-DCSK modulator.
Fig. 3 is a schematic diagram of the RCSS-DCSK demodulator.
Fig. 4 is a comparison graph of error performance of the RCSS-DCSK modem method in the embodiment and the prior art in an additive white gaussian noise channel.
Detailed Description
In order to facilitate understanding of those skilled in the art, the present invention will be further described with reference to the following embodiments and accompanying drawings.
Fig. 1 shows the whole flow of a repeatable chaotic spread spectrum DCSK (i.e. RCSS-DCSK) modulation and demodulation method, as shown in fig. 1, at a transmitting end, a signal modulation process at least includes: firstly, serial-parallel conversion is carried out on the input serial information signal. Secondly, acquiring a discrete chaotic signal sequence; delaying the discrete chaotic signal sequence to obtain a DCSK reference signal; and generating a repeatable chaotic spread spectrum sequence by using the discrete chaotic signal sequence before and after the time delay to obtain the RCSS reference signal. Dividing the information signal after serial-parallel conversion into two parallel signals; one path of parallel signals is modulated with a DCSK reference signal through a discrete chaotic signal sequence to form a DCSK signal; the other path of parallel signals is modulated through an RCSS reference signal to form an RCSS-DCSK signal; and combining the DCSK signal with the RCSS-DCSK signal and sending the combined signal to a channel for transmission. At the receiving end, the signal demodulation process at least comprises the following steps: and fourthly, respectively carrying out relevant demodulation on the received DCSK signal and the RCSS-DCSK signal, and outputting corresponding demodulation data through threshold judgment. And fifthly, converting the obtained demodulation data into a path of serial demodulation data in parallel and serial mode and outputting the demodulated data. The more detailed modem process is as follows:
step 1: a discrete chaotic signal sequence is generated.
Step 2: and (3) delaying the discrete chaotic signal sequence generated in the step (1) to obtain a DCSK reference signal.
And step 3: the signal in the current symbol period is serial-to-parallel converted into 2 parallel portions.
And 4, step 4: and (3) carrying out differential chaos shift keying modulation on the discrete chaotic signal sequence generated in the step (1), the DCSK reference signal formed in the step (2) and one part of information stream generated in the step (3) to form a DCSK signal.
And 5: and (3) generating a repeatable chaotic spread spectrum sequence by utilizing the discrete chaotic signal sequence generated in the step (1) and the discrete chaotic signal sequence delayed in the step (2) to form the RCSS reference signal.
Step 6: and multiplying the RCSS reference signal formed in the step 5 with another part of the information flow generated in the step 3 to form an RCSS-DCSK signal.
And 7: and adding the DCSK signal generated in the step 4 and the RCSS-DCSK signal generated in the step 6 and then transmitting the added DCSK signal.
And 8: and receiving the signal sent in the step 7, and performing correlation demodulation.
And step 9: comparing the correlation value obtained in the step 8 with a threshold value, and outputting a demodulation data bit according to threshold judgment;
step 10: and merging the demodulated data bits obtained in the step 9 into a path of serial demodulated data bit stream.
Based on the RCSS-DCSK modulation and demodulation method, the embodiment further designs a repeatable chaotic spread spectrum differential chaotic shift keying (RCSS-DCSK) modem, and the modem can modulate and demodulate signals by using the method. Briefly, the modulator comprises two parts, wherein one part of information signals (one part of original information signals after serial-parallel conversion) is modulated by DCSK, the other part of the information signals generates a repeatable chaotic spread spectrum sequence (RCSS) by using a chaotic signal generator, the rest information signals are modulated by the RCSS, the two parts are added and then sent to a channel, and finally, the received signals are respectively subjected to correlation operation and judgment by a demodulator, and then are subjected to parallel-serial conversion to output the information signals.
Fig. 2 and 3 show the structures of a modulator and a demodulator in an RCSS-DCSK modem, respectively. As shown in fig. 2, the modulator includes a chaotic signal generator, a delay unit 1, a serial-to-parallel conversion circuit, a multiplier 1, a multiplier 2, and an adder. The chaotic signal generator generates a discrete chaotic signal sequence, and the discrete chaotic signal sequence passes through the delayer 1 to further obtain a DCSK reference signal in the current symbol period; the serial-parallel conversion circuit converts serial data bits to be transmitted in the current symbol time into two paths of parallel data bits; the multiplier 1 multiplies one path of parallel data bits with a DCSK reference signal in the current symbol period; the multiplier 2 multiplies the RCSS reference signal by another path of parallel data bits to generate an RCSS-DCSK signal; and the adder adds the DCSK signal and the RCSS-DCSK signal and then sends the added signals.
As shown in fig. 3, the demodulator includes a delay, a multiplier 3, a multiplier 4, a summer 1, a summer 2, a sampling switch, a decision device, and a parallel-to-serial conversion circuit. The delayer delays the received DCSK signal; the multiplier 3 multiplies the delayed DCSK signal by the undelayed DCSK signal; the multiplier 4 multiplies the DCSK signal by the RCSS-DCSK signal; summer 1 is the correlation of the DCSK signal; summer 2 is the correlation of the RCSS-DCSK signal; the sampling switch respectively carries out time domain sampling on the correlated signals; the decision device compares the sampling value with a threshold value and decides to output a demodulation data bit according to the threshold value; and the parallel-serial conversion circuit combines the two paths of demodulation data bits into one path of serial demodulation data bit and outputs the serial demodulation data bit.
The bit error rate of the repeatable chaotic spread spectrum differential chaotic shift keying modulation and demodulation method is verified by a specific example.
Firstly, at a transmitting end, performing repeatable chaotic spread spectrum differential chaotic shift keying modulation on a signal:
step 1: bit SNR in a channel
Then, the length in one symbol period is obtainedkA discrete chaotic signal sequence of 15.
Step 2: delaying the discrete chaotic signal sequence generated in the step 1
。
And step 3: for the signal in the current symbol period, a serial-to-parallel conversion circuit is used to convert 1 serial data bit with the length of 5000 to be transmitted in the current symbol period into two parallel data bits with the length of 2500.
And 4, step 4: performing differential chaotic shift keying modulation on one path of information flow generated in the steps 1, 2 and 3 to generate a DCSK signal:
and 5: using the discrete chaotic signal sequence generated in step 1 and the delayed time in step 2
The subsequent discrete chaotic signal sequence generates a repeatable chaotic spread spectrum sequence to obtain an RCSS reference signal:
step 6: multiplying the RCSS reference signal obtained in step 5 with another part of the information stream generated in step 3 to generate an RCSS-DCSK signal:
and 7: and adding the DCSK signal generated in the step 4 and the RCSS-DCSK signal generated in the step 6 and then transmitting the added DCSK signal.
Then, the signal is received and demodulated at the receiving side:
and 8: and receiving the signal sent in the step 7, and performing correlation demodulation.
And step 9: and (4) comparing the correlation value obtained in the step (8) with a threshold value, and outputting a demodulated data bit according to threshold judgment.
Step 10: and combining the demodulated data bits obtained in the step 9 into a 1-path serial demodulated data bit stream.
And carrying out transmission test on the verification example by adopting computer simulation. In the experiment, the number of transmitted data bits is 5000, and a discrete chaotic signal sequence is mapped by a second-order chebyshev polynomial
And (4) generating.
Fig. 4 shows the bit error rate of the RCSS-DCSK method simulated in the additive white gaussian noise channel. For comparison, the bit error rate of the conventional DCSK method simulated under the same conditions is also shown in the figure. As can be seen from the figure, compared with the existing DCSK method, the RCSS-DCSK method greatly reduces the bit error rate and shows better bit error performance.
In summary, the RCSS-DCSK method adopted in the above embodiments greatly reduces the noise component in the decision variable, and significantly improves the bit error performance of the system. Meanwhile, the RCSS-DCSK method utilizes the discrete chaotic signal sequences before and after the delay to generate the repeatable chaotic spread spectrum sequence to obtain the RCSS reference signal, and the RCSS reference signal is used for modulating the data stream, so that the confidentiality of the high DCSK system can be improved to a certain extent, and an eavesdropper is more difficult to detect and recover the original data.
The above embodiments are preferred implementations of the present invention, and the present invention can be implemented in other ways without departing from the spirit of the present invention.
Some of the drawings and descriptions of the present invention have been simplified to facilitate the understanding of the improvements over the prior art by those skilled in the art, and some other elements have been omitted from this document for the sake of clarity, and it should be appreciated by those skilled in the art that such omitted elements may also constitute the subject matter of the present invention.
Claims (10)
1. The DCSK modulation and demodulation method is characterized in that at a sending end, signal modulation comprises the following steps:
1) performing serial-to-parallel conversion on an input serial information signal;
2) acquiring a discrete chaotic signal sequence and delaying the discrete chaotic signal sequence to obtain a DCSK reference signal; generating a repeatable chaotic spread spectrum sequence by using the discrete chaotic signal sequences before and after time delay to obtain an RCSS reference signal;
3) dividing the information signal after serial-parallel conversion into two parallel signals; one path of parallel signals is modulated with a DCSK reference signal through a discrete chaotic signal sequence to form a DCSK signal; the other path of parallel signals is modulated through an RCSS reference signal to form an RCSS-DCSK signal; and combining the DCSK signal with the RCSS-DCSK signal and sending the combined signal to a channel for transmission.
2. The repeatable chaotic spread spectrum DCSK modulation and demodulation method according to claim 1, wherein at the receiving end, the signal demodulation comprises the following steps:
4) respectively carrying out relevant demodulation on the received DCSK signal and the RCSS-DCSK signal, and outputting corresponding demodulation data through threshold judgment;
5) and converting the obtained demodulation data into a path of serial demodulation data in parallel and serial mode and outputting the demodulated data.
3. The repeatable chaotic spread spectrum DCSK modulation and demodulation method according to claim 1 or 2, wherein: in step 1), the input serial information in the current symbol period is converted in serial-to-parallel.
4. The repeatable chaotic spread spectrum DCSK modulation and demodulation method according to claim 3, wherein: in the step 2), a discrete chaotic signal sequence is generated by the chaotic signal generator, and then the discrete chaotic signal sequence generated by the chaotic signal generator is obtained.
5. The repeatable chaotic spread spectrum DCSK modem method according to claim 4, wherein in step 3):
when one of the parallel signals is modulated through the discrete chaotic signal sequence and the DCSK reference signal, multiplying the DCSK reference signal in the current symbol period by the corresponding parallel signal to obtain a DCSK information signal, and modulating the DCSK information signal through the discrete chaotic signal sequence to form a DCSK signal;
when the RCSS reference signal is used for modulating the other path of parallel signal, the RCSS reference signal is multiplied by the corresponding parallel signal to obtain an RCSS-DCSK signal;
and when the DCSK signal and the RCSS-DCSK signal are combined, the DCSK signal and the RCSS-DCSK signal are added.
6. The repeatable chaotic spread spectrum DCSK modem method according to claim 2, wherein in step 4):
when carrying out correlation demodulation on the DCSK signal, delaying the received DCSK signal, multiplying the delayed DCSK signal by the undelayed DCSK signal, carrying out correlation processing, carrying out time domain sampling on the correlated signal, comparing a sampling value with a threshold value, and outputting demodulation data according to threshold judgment;
when the RCSS-DCSK signal is subjected to correlation demodulation, the received RCSS-DCSK signal and the DCSK signal which is not delayed are multiplied, then correlation processing is carried out, time domain sampling is carried out on the correlated signal, then the sampling value is compared with a threshold value, and demodulation data are output according to threshold decision.
7. The repeatable chaos spread spectrum DCSK modem comprises a modulator and a demodulator, and is characterized in that: the modulator modulates the input serial information signal according to the method of steps 1) to 3) of claim 1.
8. The repeatable chaotic spread spectrum DCSK modem according to claim 7, wherein: the demodulator demodulates the received signal in accordance with the method of steps 4) to 5) of claim 2.
9. The repeatable chaotic spread spectrum DCSK modem according to claim 8, wherein: the modulator comprises a chaotic signal generator, a delayer 1, a serial-parallel conversion circuit, a multiplier 1, a multiplier 2 and an adder;
the chaotic signal generator is used for generating a discrete chaotic signal sequence, the discrete chaotic signal sequence is delayed by the delayer 1 to obtain a DCSK reference signal in the current symbol period, and then the discrete chaotic signal sequence before and after delay is utilized to generate an RCSS reference signal; the serial-parallel conversion circuit converts serial information signals to be transmitted in the current symbol period into two parallel signals; the multiplier 1 multiplies a DCSK reference signal in a current symbol period by one of the parallel signals; the multiplier 2 multiplies the RCSS reference signal by another parallel signal; and the adder adds the DCSK signal and the RCSS-DCSK signal and then sends the added signals to a channel for transmission.
10. The repeatable chaotic spread spectrum DCSK modem according to claim 8 or 9, wherein: the demodulator comprises a delayer 2, a multiplier 3, a multiplier 4, a summer 1, a summer 2, a sampling switch, a decision device and a parallel-serial conversion circuit;
the delayer delays the received DCSK signal; the multiplier 3 multiplies the delayed DCSK signal by the undelayed DCSK signal; the multiplier 4 multiplies the RCSS-DCSK signal by the DCSK signal without time delay; the summer 1 is a correlation of the DCSK signal; the summer 2 is the correlation of the RCSS-DCSK signal; the sampling switch respectively carries out time domain sampling on the correlated signals; the decision device compares the sampling value with a threshold value and outputs a demodulation data bit according to threshold decision; and the parallel-serial conversion circuit converts the two obtained paths of demodulation data into one path of serial demodulation data in parallel-serial mode and outputs the demodulated data.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110323912.2A CN113055154B (en) | 2021-03-26 | 2021-03-26 | Repeatable chaos spread spectrum DCSK modulation and demodulation method and modem |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110323912.2A CN113055154B (en) | 2021-03-26 | 2021-03-26 | Repeatable chaos spread spectrum DCSK modulation and demodulation method and modem |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113055154A CN113055154A (en) | 2021-06-29 |
| CN113055154B true CN113055154B (en) | 2022-04-22 |
Family
ID=76515617
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110323912.2A Active CN113055154B (en) | 2021-03-26 | 2021-03-26 | Repeatable chaos spread spectrum DCSK modulation and demodulation method and modem |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113055154B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114095147B (en) * | 2021-11-29 | 2023-08-18 | 湖南科技大学 | Electronic lock secret communication method based on five-dimensional false fractional order and chaotic shift keying |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105187347A (en) * | 2015-09-30 | 2015-12-23 | 南京邮电大学 | Multivariate orthogonal chaos shift keying modulation/demodulation method |
| CN106161310A (en) * | 2016-07-21 | 2016-11-23 | 南京邮电大学 | A kind of multicarrier difference chaotic shift keying modulation demodulation method and modem |
| CN106341221A (en) * | 2016-09-05 | 2017-01-18 | 中山大学 | Repetitive correlation delay shift keying method for improving performance of wireless chaos communication system |
| CN111770040A (en) * | 2020-06-16 | 2020-10-13 | 重庆邮电大学 | Improved multi-user DCSK chaotic communication system |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100618389B1 (en) * | 2005-03-07 | 2006-09-01 | 삼성전자주식회사 | Wide band-dcsk modulation method, transmitting apparatus thereof, wide band-dcsk demodulation method, receiving apparatus thereof |
| WO2018200591A1 (en) * | 2017-04-24 | 2018-11-01 | Chaos Prime, Inc. | Communication system employing chaotic sequence based frequency shift keying spreading signals |
-
2021
- 2021-03-26 CN CN202110323912.2A patent/CN113055154B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105187347A (en) * | 2015-09-30 | 2015-12-23 | 南京邮电大学 | Multivariate orthogonal chaos shift keying modulation/demodulation method |
| CN106161310A (en) * | 2016-07-21 | 2016-11-23 | 南京邮电大学 | A kind of multicarrier difference chaotic shift keying modulation demodulation method and modem |
| CN106341221A (en) * | 2016-09-05 | 2017-01-18 | 中山大学 | Repetitive correlation delay shift keying method for improving performance of wireless chaos communication system |
| CN111770040A (en) * | 2020-06-16 | 2020-10-13 | 重庆邮电大学 | Improved multi-user DCSK chaotic communication system |
Non-Patent Citations (1)
| Title |
|---|
| 调频相关延迟差分混沌键控的通信模型及性能;王娟等;《黑龙江科技大学学报》;20160930(第05期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113055154A (en) | 2021-06-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106161310B (en) | A kind of multicarrier difference chaotic shift keying modulation demodulation method and modem | |
| CN108365945B (en) | Differential chaotic shift keying modem and method based on two-way index modulation | |
| US8644362B1 (en) | Hybrid pseudo-random noise and chaotic signal implementation for covert communication | |
| Ramavath et al. | Analytical calculations of CCDF for some common PAPR reduction techniques in OFDM systems | |
| US7924941B2 (en) | Digital pre-distortion for orthogonal frequency division multiplexing (OFDM) signals | |
| JP2005509365A (en) | Apparatus and method for reducing peak power versus average power in an orthogonal frequency division multiplexing mobile communication system | |
| CN103905358A (en) | Improved type differential chaos shift keying DCSK confidentiality communication method | |
| Wu et al. | Modulation detection of underwater acoustic communication signals through cyclostationary analysis | |
| CN113890805B (en) | Multi-user multi-carrier CDSK chaotic communication method and system with high transmission rate | |
| KR100480268B1 (en) | Apparatus and method for papr reduction in ofdm system | |
| CN115550127A (en) | Carrier index multi-system chaotic modulation and demodulation method based on code shift and modem | |
| Cai et al. | Design and performance analysis of differential chaos shift keying system with dual-index modulation | |
| CN113630356B (en) | Fractional order multi-carrier multi-code shift multi-system differential chaos shift keying modulation and demodulation method and modem | |
| CN113055154B (en) | Repeatable chaos spread spectrum DCSK modulation and demodulation method and modem | |
| KR102424821B1 (en) | A TRANSMITTER AND RECEIVER OF SUPPORTING A LOW PAPR(Peak-to-Average Power Ratio) AND METHOD FOR THE SAME | |
| Afifi et al. | An efficient technique for out-of-band power reduction for the eliminated CP-STC-shaped system for 5G requirements | |
| CN116405360A (en) | High data rate carrier index differential chaos keying modulation and demodulation method and system based on scrambling matrix | |
| CN106357383B (en) | DC-DCSK secret communication system and analysis processing method | |
| Hasan | Design and analysis of an orthogonal chaotic vectors based differential chaos shift keying communication system | |
| Kamboj et al. | Study & Simulation of OFDM system | |
| Zhang et al. | Multi-user high rate security differential chaos shift keying | |
| Berber et al. | Theoretical modeling and simulation of a chaos-based physical layer for WSNS | |
| CN118677735B (en) | Code shift differential chaos shift keying modulation and demodulation method and modulator-demodulator | |
| CN111525976A (en) | Hidden communication method based on normal random process mean parameter modulation | |
| CN111817993A (en) | Improved short reference correlation delay shift keying communication scheme |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20240527 Address after: No. 11-12 Dawangjia Lane, Xiangya Road Street, Kaifu District, Changsha City, Hunan Province, 410153, Room 701, Wenchangge West, Area A, No. 48 Patentee after: Hunan Hongjing Information Technology Co.,Ltd. Country or region after: China Address before: 421002 Hunan city of Hengyang province Zhuhui District Road No. 18 Hua Heng Patentee before: HUNAN INSTITUTE OF TECHNOLOGY Country or region before: China |