CN112653489A - Narrow-band frequency hopping radio signal identification method - Google Patents
Narrow-band frequency hopping radio signal identification method Download PDFInfo
- Publication number
- CN112653489A CN112653489A CN202110069805.1A CN202110069805A CN112653489A CN 112653489 A CN112653489 A CN 112653489A CN 202110069805 A CN202110069805 A CN 202110069805A CN 112653489 A CN112653489 A CN 112653489A
- Authority
- CN
- China
- Prior art keywords
- frequency hopping
- radio signals
- frequency
- signals
- sides
- 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.)
- Pending
Links
Images
Classifications
-
- 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
- H04B1/713—Spread spectrum techniques using frequency hopping
-
- 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
- H04B1/713—Spread spectrum techniques using frequency hopping
- H04B1/715—Interference-related aspects
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04K—SECRET COMMUNICATION; JAMMING OF COMMUNICATION
- H04K3/00—Jamming of communication; Counter-measures
- H04K3/20—Countermeasures against jamming
- H04K3/22—Countermeasures against jamming including jamming detection and monitoring
Abstract
The invention discloses a narrowband frequency hopping radio signal identification method, which is characterized in that radio signals of preset frequency and adjacent frequencies on two sides of the radio signals are detected and demodulated at the same time or in a short time interval, the preset frequency of the narrowband frequency hopping radio signals and the power corresponding to the radio signals of the adjacent frequencies on two sides of the radio signals are compared, when the power corresponding to the radio signals of the adjacent frequencies on two sides is smaller than a first threshold value of the power corresponding to the preset frequency of the narrowband frequency hopping radio signals and the power difference corresponding to the radio signals of the adjacent frequencies on two sides is smaller than a second threshold value, the narrowband frequency hopping radio signals are judged to be legal signals, and otherwise, the narrowband frequency hopping radio signals are illegal signals. It is possible to effectively distinguish whether a signal to be received is a frequency hopping radio signal transmitted by a legitimate transmitter at a predetermined frequency or a fixed frequency radio signal covering the entire frequency band transmitted by an illegitimate transmitter. The application of frequency hopping radio communication to increase security can be extended to the field of narrowband wireless communication.
Description
Technical Field
The invention relates to the technical field of identification of narrowband frequency hopping radio signals, in particular to a narrowband frequency hopping radio signal identification method.
Background
A transmitter of a prior art frequency hopping communication performs information modulation (first modulation) on a carrier signal and a second modulation (frequency modulation according to a predetermined frequency sequence) on a modulated carrier, and the receiver tunes reception according to the same frequency sequence. For civil communication, because of the limited frequency range allowed by regulations, an illegal transmitter can receive the illegal signal no matter whether the receiver is tuned to any frequency point in the allowed frequency range by transmitting a radio signal covering the whole allowed frequency range, therefore, the signal can be disguised as a legal transmitter without knowing a predetermined frequency hopping sequence, the existing frequency hopping receiver can always receive the signal of the transmitter according to the predetermined frequency hopping sequence, the safety caused by frequency hopping is lost in the communication process, such as wireless communication between a vehicle and a remote control key, if frequency hopping communication is adopted, the difficulty and cost of relay attack can be well increased, but for the receiving mode of the existing receiver, if an illegal transmitter replaces a frequency hopping transmitter with a frequency band covering the entire regulatory permit, it is easily disguised as a legitimate signal.
Disclosure of Invention
The invention aims to provide a narrow-band frequency hopping radio signal identification method for effectively distinguishing authenticity.
The invention relates to a narrowband frequency hopping radio signal identification method, which comprises the following steps:
detecting and demodulating radio signals of a predetermined frequency of a narrowband frequency hopping radio signal and adjacent frequencies on both sides thereof at the same time or in a short time interval;
comparing the preset frequency of the narrow-band frequency hopping radio signal and the power corresponding to the radio signals of adjacent frequencies on two sides of the preset frequency;
and when the power corresponding to the radio signals with adjacent frequencies on two sides is smaller than a first threshold value of the power corresponding to the preset frequency of the radio signals with adjacent frequencies on two sides and the power difference corresponding to the radio signals with adjacent frequencies on two sides is smaller than a second threshold value, judging that the radio signals with adjacent frequencies on the two sides are legal radio signals with frequency hopping, and otherwise, judging that the radio signals with frequency hopping are illegal signals.
The invention relates to a method for identifying a narrow-band frequency hopping radio signal, which is characterized in that a radio signal adopting a narrow-band frequency hopping technology can be quickly attenuated outside a communication bandwidth, the energy of a disguised radio signal can cover a communication frequency band allowed by the whole regulation, signals of adjacent frequency points on two sides of a preset frequency are not obviously attenuated, a receiver simultaneously receives the narrow-band frequency hopping radio signal and signals of two frequency points with higher and lower preset frequencies, and the narrow-band frequency hopping radio signal can be judged to be a legal narrow-band frequency hopping signal by comparing the power corresponding to the narrow-band frequency hopping radio signal and the adjacent frequency signals on two sides of the narrow-band frequency hopping radio signal when the corresponding power of the adjacent frequency signals on two sides is less than a first threshold value of the power corresponding to the frequency of the narrow-band frequency hopping radio signal and the power difference corresponding to the adjacent frequency signals on two sides is less than, the illegal signals are prevented from being disguised as legal signals, so that the safety of receiving the narrow-band frequency hopping radio signals by the user equipment is improved.
Drawings
Fig. 1 is a diagram illustrating the identification of power corresponding to three frequencies by a narrowband frequency hopping radio signal according to the present invention.
Detailed Description
As shown in fig. 1, a narrowband frequency hopping radio signal identification method includes the steps of:
by hopping predetermined frequencies (f) of the radio signal simultaneously or within short time intervals0) And its two side adjacent frequencies (f)0-f1,f0+f1) Detecting and demodulating the radio signal;
comparing the preset frequency of the narrow-band frequency hopping radio signal and the power corresponding to the radio signals of adjacent frequencies on two sides of the preset frequency;
and when the power corresponding to the radio signals with adjacent frequencies on two sides is smaller than a first threshold value of the power corresponding to the preset frequency of the narrow-band frequency hopping radio signal and the power difference corresponding to the radio signals with adjacent frequencies on two sides is smaller than a second threshold value, judging that the radio signals are legal narrow-band frequency hopping signals, otherwise, judging that the radio signals are illegal signals.
The first threshold is 10-50 dB, the second threshold is 1-10 dB, f0 can be arbitrarily selected in a radio wave range, and f1 is 0.01% -1% of f 0.
For example, the transmitter is prepared to transmit a radio signal by frequency hopping in the 430 MHz to 440MHz band, and the 435MHz carrier is signal-modulated with a signal to be transmitted, and then the signal-modulated 435MHz carrier is frequency-modulated so that the carrier frequency is changed between the 430 MHz to 440MHz bands in a predetermined sequence, for example, 430.05MHz → 431.00MHz → 433.05MHz → 438.99MHz → …, and at this time, the receiver adjusts the reception frequency in the same sequence, and tunes reception in the order of 430.05MHz → 431.00MHz → 433.05MHz → 438.99MHz → …. However, in addition to detecting the power value of the corresponding frequency of each predetermined sequence, the power value of a frequency slightly higher or lower than the corresponding frequency of the predetermined sequence should be measured simultaneously or in a short time, for example, 430.00MHz/430.55MHz → 430.50MHz/431.50MHz → 432.55MHz/433.55MHz → 438.49MHz/439.49 MHz → … corresponding to the above-mentioned frequency sequence, when the power of the corresponding slightly higher or lower frequency is significantly lower than the power of the corresponding frequency of the predetermined sequence, for example, 30 dB, and the difference between the power of the corresponding slightly higher and lower frequency is small, for example, 3dB, the corresponding narrowband frequency hopping signal is considered as being transmitted by a legitimate transmitter, otherwise, the corresponding spurious signal is probably transmitted by an illegitimate transmitter.
The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.
Claims (3)
1. A narrowband frequency hopping radio signal identification method, comprising the steps of:
detecting and demodulating radio signals of a predetermined frequency of a narrowband frequency hopping radio signal and adjacent frequencies on both sides thereof at the same time or in a short time interval;
comparing the preset frequency of the narrow-band frequency hopping radio signal and the power corresponding to the radio signals of adjacent frequencies on two sides of the preset frequency;
and when the power corresponding to the radio signals with adjacent frequencies on two sides is smaller than a first threshold value of the power corresponding to the preset frequency of the radio signals with adjacent frequencies on two sides and the power difference corresponding to the radio signals with adjacent frequencies on two sides is smaller than a second threshold value, judging that the radio signals with adjacent frequencies on the two sides are legal radio signals with frequency hopping, and otherwise, judging that the radio signals with frequency hopping are illegal signals.
2. The narrowband frequency hopping radio signal identification method of claim 1, wherein the first threshold value is 10-50 dB.
3. The narrowband frequency hopping radio signal identification method of claim 1, wherein the second threshold is 1-10 dB.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110069805.1A CN112653489A (en) | 2021-01-19 | 2021-01-19 | Narrow-band frequency hopping radio signal identification method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110069805.1A CN112653489A (en) | 2021-01-19 | 2021-01-19 | Narrow-band frequency hopping radio signal identification method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112653489A true CN112653489A (en) | 2021-04-13 |
Family
ID=75370570
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110069805.1A Pending CN112653489A (en) | 2021-01-19 | 2021-01-19 | Narrow-band frequency hopping radio signal identification method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112653489A (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6327312B1 (en) * | 1998-06-24 | 2001-12-04 | Intermec Ip Corp. | RF narrowband/wideband discriminating system for spread spectrum signal differentiation |
| CN1533048A (en) * | 2002-09-30 | 2004-09-29 | ض� | Identifying method for IEEE 802.11b radio signal |
| US20040198363A1 (en) * | 2003-01-13 | 2004-10-07 | Ray Zinn | Wireless device and method using frequency hopping and sweep modes |
| CN101616508A (en) * | 2008-06-25 | 2009-12-30 | 大唐移动通信设备有限公司 | Frequency points of wireless communication system scan method and device |
| CN103501205A (en) * | 2013-10-11 | 2014-01-08 | 北京理工大学 | Target frequency hopping signal identification method based on fuzzy comprehensive evaluation |
| CN105991492A (en) * | 2015-02-10 | 2016-10-05 | 北京空间飞行器总体设计部 | Frequency hopping (FH) signal identification method |
| CN106656226A (en) * | 2016-12-06 | 2017-05-10 | 大唐半导体设计有限公司 | Narrowband interference processing method and device |
-
2021
- 2021-01-19 CN CN202110069805.1A patent/CN112653489A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6327312B1 (en) * | 1998-06-24 | 2001-12-04 | Intermec Ip Corp. | RF narrowband/wideband discriminating system for spread spectrum signal differentiation |
| CN1533048A (en) * | 2002-09-30 | 2004-09-29 | ض� | Identifying method for IEEE 802.11b radio signal |
| US20040198363A1 (en) * | 2003-01-13 | 2004-10-07 | Ray Zinn | Wireless device and method using frequency hopping and sweep modes |
| CN101616508A (en) * | 2008-06-25 | 2009-12-30 | 大唐移动通信设备有限公司 | Frequency points of wireless communication system scan method and device |
| CN103501205A (en) * | 2013-10-11 | 2014-01-08 | 北京理工大学 | Target frequency hopping signal identification method based on fuzzy comprehensive evaluation |
| CN105991492A (en) * | 2015-02-10 | 2016-10-05 | 北京空间飞行器总体设计部 | Frequency hopping (FH) signal identification method |
| CN106656226A (en) * | 2016-12-06 | 2017-05-10 | 大唐半导体设计有限公司 | Narrowband interference processing method and device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP3037306B1 (en) | Method for preventing relay attack on vehicle smart key system | |
| US6763315B2 (en) | Method of securing access to a user having an enhanced security proximity token | |
| US6943725B2 (en) | Access control system with limited evaluation of code and distance information | |
| US20060273888A1 (en) | Radio Communication System and Radio Communication Device | |
| US20060273887A1 (en) | Radio Communication System and Radio Communication Device | |
| RU2214049C2 (en) | Data transmission and reception method, system, and receiver | |
| US20140215567A1 (en) | Communication system and communication device | |
| US9203467B2 (en) | Method of management for operating a broad band communication system and a narrow band communication system implemented in a same frequency band | |
| Joo et al. | Hold the door! fingerprinting your car key to prevent keyless entry car theft | |
| US20040137877A1 (en) | Security system | |
| US9035757B2 (en) | Communication system and communication device | |
| CA2244583A1 (en) | Frequency-hopping spread-spectrum radio communications | |
| WO2003061149A1 (en) | Frequency hopping spread spectrum communications system | |
| JP2002198837A (en) | Cancellation of interference of narrow band interferer in wide band wireless device | |
| CA2817117A1 (en) | Method of detecting and jamming transmitter effecting a communication user equipment, user equipment and evaluation unit with interfaces to the user equipment | |
| JP6768161B2 (en) | Protection against relay attacks | |
| GB2311155A (en) | Anti-theft system for a motor vehicle | |
| US20200309941A1 (en) | Distance-measuring system, distance-measuring device and distance-measuring method | |
| US20170320465A1 (en) | Anti-theft remote keyless entry system using frequency hopping with amplitude level control | |
| JP4448618B2 (en) | Entry system | |
| US20130259165A1 (en) | Circuit and method for distinguishing between an ofdm signal and a radar signal | |
| CN112653489A (en) | Narrow-band frequency hopping radio signal identification method | |
| US9600948B2 (en) | Keyless entry apparatus | |
| US7336695B1 (en) | m-ary variable shift keying communications system | |
| EP3902148A1 (en) | Communication system having selectable hopping rate and hopping frequency window and associated methods |
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 | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210413 |
|
| RJ01 | Rejection of invention patent application after publication |