Method and device for transmitting and receiving digital signal sequence

Abstract

The present invention discloses a method and device for transmitting and receiving a digital signal sequence, wherein the transmitting method comprises the following steps: receiving a digital signal sequence S(t), modulating the digital signal sequence S(t) to obtain a digital signal sequence C(t); generating noise in a preset frequency range, wherein the preset frequency range includes the frequency range of the digital signal sequence S(t); processing the noise based on a notch filter to obtain a signal N(t); coupling the digital signal sequence C(t) and the signal N(t) to obtain a signal B(t), and transmitting the signal B(t) after radio frequency modulation. The transmitting method has a strong anti-interference capability.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a method and a device for transmitting and receiving a digital signal sequence. Background Art

[0002] The quality of wireless communication links may be affected by many factors, such as transmission delay, signal-to-noise ratio, etc. Changes in these factors may lead to instability of the communication link. In particular, if someone deliberately interferes with the communication channel, the quality of the wireless communication link will be further degraded.

[0003] Therefore, when the communication channel is interfered, how to ensure smooth wireless communication becomes an urgent problem to be solved. Summary of the invention

[0004] In view of this, the main purpose of the present invention is to provide a method and device for transmitting and receiving a digital signal sequence.

[0005] To achieve the above-mentioned purpose, the technical solution of the present invention is implemented as follows: a method for transmitting a digital signal sequence, comprising the following steps: receiving a digital signal sequence S(t), modulating the digital signal sequence S(t) to obtain a digital signal sequence C(t); generating noise in a preset frequency range, wherein the preset frequency range includes the frequency range of the digital signal sequence S(t); processing the noise based on a notch filter to obtain a signal N(t); coupling the digital signal sequence C(t) and the signal N(t) to obtain a signal B(t), and transmitting the signal B(t) after radio frequency modulation.

[0006] As an improvement of an embodiment of the present invention, the "modulating the digital signal sequence S(t) to obtain the digital signal sequence C(t)" specifically includes: modulating the digital signal sequence S(t) based on single-frequency FSK to obtain the digital signal sequence C(t).

[0007] As an improvement of the embodiment of the present invention, the “generating noise within a preset frequency range” specifically includes: using a white noise generator to generate noise within a preset frequency range.

[0008] As an improvement to the embodiment of the present invention, the frequency of the single-frequency FSK is f, the bandwidth of the digital signal sequence S(t) is b, and the frequency spectrum range of the digital signal sequence C(t) is [fb, f+b].

[0009] The embodiment of the present invention also provides a digital signal sequence transmitting device, comprising the following steps: a signal receiving module, used to receive a digital signal sequence S(t), and modulate the digital signal sequence S(t) to obtain a digital signal sequence C(t); a noise generating module, used to generate noise in a preset frequency range, wherein the preset frequency range includes the frequency range of the digital signal sequence S(t); processing the noise based on a notch filter to obtain a signal N(t); and a coupling module, used to couple the digital signal sequence C(t) and the signal N(t) to obtain a signal B(t), and transmit the signal B(t) after radio frequency modulation.

[0010] As an improvement of the embodiment of the present invention, the signal receiving module is further used to: modulate the digital signal sequence S(t) based on single-frequency FSK to obtain a digital signal sequence C(t).

[0011] As an improvement of the embodiment of the present invention, the noise generating module is further used to: use a white noise generator to generate noise in a preset frequency range.

[0012] As an improvement to the embodiment of the present invention, the frequency of the single-frequency FSK is f, the bandwidth of the digital signal sequence S(t) is b, and the frequency spectrum range of the digital signal sequence C(t) is [fb, f+b].

[0013] An embodiment of the present invention also provides a method for receiving a digital signal sequence, comprising the following steps: receiving a radio frequency signal, performing narrowband filtering on the radio frequency signal to obtain a signal B′(t), performing demodulation processing and baseband filtering processing on the signal B′(t) to obtain a signal S′(t); performing modulation processing and shaping processing on the signal S′(t) to obtain a digital signal sequence.

[0014] An embodiment of the present invention also provides a device for receiving a digital signal sequence, comprising the following modules: a first processing module, used to receive a radio frequency signal, perform narrowband filtering on the radio frequency signal to obtain a signal B′(t), and perform demodulation processing and baseband filtering on the signal B′(t) to obtain a signal S′(t); a second processing module, used to perform modulation processing and shaping processing on the signal S′(t) to obtain a digital signal sequence.

[0015] The digital signal sequence transmission and receiving method and device provided by the embodiment of the present invention have the following advantages: The embodiment of the present invention discloses a digital signal sequence transmission and receiving method and device, the transmission method comprises the following steps: receiving a digital signal sequence S(t), modulating the digital signal sequence S(t) to obtain a digital signal sequence C(t); generating noise in a preset frequency range, the preset frequency range includes the frequency range of the digital signal sequence S(t); processing the noise based on a notch filter to obtain a signal N(t); coupling the digital signal sequence C(t) and the signal N(t) to obtain a signal B(t), and transmitting the signal B(t) after radio frequency modulation. The transmission method has a strong anti-interference ability. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic flow chart of a method for transmitting a digital signal sequence in an embodiment of the present invention;

[0017] Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 , Fig. 9 , Fig.10 , Fig.11 and Fig.12 4 is a schematic diagram of a method for transmitting a digital signal sequence in an embodiment of the present invention. DETAILED DESCRIPTION

[0018] The present invention will be described in detail below in conjunction with the embodiments shown in the accompanying drawings. However, the embodiments do not limit the present invention, and any structural, methodological, or functional changes made by a person skilled in the art based on the embodiments are all within the protection scope of the present invention.

[0019] The following description and accompanying drawings fully illustrate the specific embodiments of this article so that those skilled in the art can practice them. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. The scope of the embodiments of this article includes the entire scope of the claims, as well as all available equivalents of the claims. Herein, the terms "first", "second", etc. are only used to distinguish one element from another, without requiring or implying any actual relationship or order between these elements. In fact, the first element can also be called the second element, and vice versa. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that the structure, device or equipment including a series of elements includes not only those elements, but also other elements that are not explicitly listed, or also include elements inherent to such structure, device or equipment. In the absence of more restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the structure, device or equipment including the elements. Each embodiment is described in a progressive manner herein, and each embodiment focuses on the differences from other embodiments, and the same and similar parts between the embodiments can be referred to each other.

[0020] The terms "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. in this document indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing this document and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of this document, unless otherwise specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a mechanical connection or an electrical connection, it can also be the internal communication of two elements, it can be a direct connection, or it can be indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0021] Embodiment 1 of the present invention provides a method for transmitting a digital signal sequence, such as Figure 1 As shown, the following steps are included:

[0022] Step 101: receiving a digital signal sequence S(t), and performing modulation processing on the digital signal sequence S(t) to obtain a digital signal sequence C(t);

[0023] Step 102: generating noise in a preset frequency range, wherein the preset frequency range includes the frequency range of the digital signal sequence S(t); and processing the noise based on a notch filter to obtain a signal N(t);

[0024] Here, a white noise generator can be used to generate noise in a preset frequency range. The preset frequency range is a wider frequency range. The energy of the noise is evenly distributed within the preset frequency spectrum, and the frequency spectrum covers the entire communication bandwidth, such as the frequency domain graph shown in FIG. Figure 4 As shown. A white noise generator is a device that uses a stable diode as a noise source and can generate white noise within a certain frequency range. The noise can be white noise. White noise refers to noise with a power spectrum density that is uniformly distributed throughout the frequency domain. Random noise with the same energy density at all frequencies is called white noise. A white noise transmitter is a device that uses a stable diode as a noise source and can generate white noise within a certain frequency range. The thermal noise of a resistor is a good white noise signal source. It has a uniform power spectrum and a signal strength of microvolts.

[0025] A notch filter is a filter that can quickly attenuate the input signal at a certain frequency point to achieve the filtering effect of blocking the signal of this frequency from passing through. A notch filter is a type of band-stop filter, but its stopband is very narrow and the starting order must be second order (including second order) or above. The center frequency of the notch filter is f, the bandwidth is 2b, and the frequency domain characteristics are as follows: Figure 5 shown.

[0026] After the noise is processed by the notch filter, the notch filter filters out the signal with a specific frequency of the noise center frequency f and bandwidth 2b, and the spectrum characteristics become as follows Figure 6 shown.

[0027] Step 103: The digital signal sequence C(t) and the signal N(t) are coupled to obtain a signal B(t), and the signal B(t) is transmitted after being subjected to radio frequency modulation.

[0028] Figure 7 The spectrum of the signal B(t) is shown in Figure 2. After being modulated by radio frequency, (t) is transmitted. The spectrum captured by the spectrum analyzer is as follows: Figure 8 shown.

[0029] In the inventor's practice, it was found that the real signal was hidden in the noise. The envelope of the signal could not be detected in the time domain, and the frequency of the real signal could not be determined in the frequency domain. When the enemy detects this signal, it often uses narrow-band Gaussian white noise for interference, and its interference power is evenly distributed in the frequency band to be interfered. Since the power of the jammer is limited, the power of the broadband noise will decrease with the increase of the bandwidth, and the interference signal that falls within the bandwidth of the real signal will be even smaller.

[0030] In this embodiment, the “modulating the digital signal sequence S(t) to obtain the digital signal sequence C(t)” specifically includes: modulating the digital signal sequence S(t) based on single-frequency FSK to obtain the digital signal sequence C(t).

[0031] FSK (Frequency-Shift Keying) is an early modulation method used in information transmission. Its main advantages are that it is easy to implement and has good noise and attenuation resistance. It has been widely used in medium and low-speed data transmission. The most common is the dual-frequency FSK system that uses two frequencies to carry binary 1 and 0.

[0032] The waveforms before and after modulation are as follows Figure 2 As shown, assuming that the frequency of FSK is f and the bandwidth of the digital signal sequence S(t) is b, the spectrum range of the digital signal sequence C(t) is f±b, as shown in Figure 3 As shown,

[0033] In this embodiment, “generating noise within a preset frequency range” specifically includes: using a white noise generator to generate noise within a preset frequency range.

[0034] In this embodiment, the frequency of the single-frequency FSK is f, the bandwidth of the digital signal sequence S(t) is b, and the frequency spectrum range of the digital signal sequence C(t) is [fb, f+b].

[0035] Embodiment 2 of the present invention provides a device for transmitting a digital signal sequence, comprising the following modules:

[0036] A signal receiving module, used for receiving a digital signal sequence S(t), and performing modulation processing on the digital signal sequence S(t) to obtain a digital signal sequence C(t);

[0037] A noise generating module, configured to generate noise within a preset frequency range, wherein the preset frequency range includes the frequency range of the digital signal sequence S(t); and to process the noise based on a notch filter to obtain a signal N(t);

[0038] The coupling module is used to couple the digital signal sequence C(t) and the signal N(t) to obtain the signal B(t), and transmit the signal B(t) after radio frequency modulation.

[0039] In this embodiment, the signal receiving module is further used to: modulate the digital signal sequence S(t) based on single-frequency FSK to obtain a digital signal sequence C(t).

[0040] In this embodiment, the noise generating module is further configured to: use a white noise generator to generate noise within a preset frequency range.

[0041] In this embodiment, the frequency of the single-frequency FSK is f, the bandwidth of the digital signal sequence S(t) is b, and the frequency spectrum range of the digital signal sequence C(t) is [fb, f+b].

[0042] Embodiment 3 of the present invention provides a method for receiving a digital signal sequence, comprising the following steps:

[0043] Step 1: Receive a radio frequency signal, perform narrowband filtering on the radio frequency signal to obtain a signal B′(t), and perform demodulation and baseband filtering on the signal B′(t) to obtain a signal S′(t);

[0044] Step 2: Perform modulation and shaping processing on the signal S′(t) to obtain a digital signal sequence.

[0045] Embodiment 4 of the present invention provides a device for receiving a digital signal sequence, comprising the following modules:

[0046] A first processing module is used to receive a radio frequency signal, perform narrowband filtering on the radio frequency signal to obtain a signal B′(t), and perform demodulation processing and baseband filtering processing on the signal B′(t) to obtain a signal S′(t);

[0047] The second processing module is used to perform modulation processing and shaping processing on the signal S′(t) to obtain a digital signal sequence.

[0048] Here, the RF signal can be received through the antenna, and the narrowband filter can filter out most of the interference signals. However, due to the high RF frequency, the narrowband filter bandwidth is difficult to achieve the bandwidth of the real signal, and some out-of-band noise will enter the signal B′(t). The spectrum after filtering will be wider than the spectrum of the real signal, such as Fig. 9 shown.

[0049] After demodulation, the signal B′(t) becomes a baseband signal, which is then filtered. Since the baseband signal frequency is low, the bandwidth is almost the same as the real signal bandwidth, so the out-of-band noise can be filtered out, but there is still a small amount of in-band noise. The time domain waveform of S′(t) is as follows: Fig.10 shown.

[0050] The time domain waveform of the signal after the modulation processing of signal S′(t) is as follows Fig.11 As shown, after reshaping, the original digital sequence signal can be restored, and the waveform is as follows Fig.12 shown.

[0051] It should be noted that although the above describes the various steps in a specific order, it does not mean that the various steps must be executed in the above specific order. In fact, some of these steps can be executed concurrently or even in a different order as long as the required functions can be achieved.

[0052] The present invention may be a system, a method and / or a computer program product. The computer program product may include a readable storage medium carrying computer readable program instructions for causing a processor to implement various aspects of the present invention.

[0053] The readable storage medium can be a tangible device that holds and stores the instructions used by the instruction execution device. The readable storage medium can include, for example, but is not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination thereof. More specific examples (non-exhaustive list) of readable storage media include: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a static random access memory (SRAM), a portable compact disk read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanical encoding device, for example, a punch card or a protruding structure in a groove on which instructions are stored, and any suitable combination thereof.

[0054] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A method for transmitting a digital signal sequence, characterized in that: The following steps are involved: Receiving a digital signal sequence S(t), and performing modulation processing on the digital signal sequence S(t) to obtain a digital signal sequence C(t); Generate noise in a preset frequency range, where the preset frequency range includes the frequency range of the digital signal sequence S(t); process the noise based on a notch filter to obtain a signal N(t); The digital signal sequence C(t) and the signal N(t) are coupled to obtain the signal B(t), and the signal B(t) is transmitted after being modulated by radio frequency.

2. The transmitting method according to claim 1, characterized in that: The “modulating the digital signal sequence S(t) to obtain the digital signal sequence C(t)” specifically includes: The digital signal sequence S(t) is modulated based on single-frequency FSK to obtain a digital signal sequence C(t).

3. The transmitting method according to claim 2, characterized in that: The “generating noise within a preset frequency range” specifically includes: Use the white noise generator to generate noise in a preset frequency range.

4. The transmitting method according to claim 2, characterized in that: The frequency of single-frequency FSK is f, the bandwidth of the digital signal sequence S(t) is b, and the spectrum range of the digital signal sequence C(t) is [fb,f+b].

5. A digital signal sequence transmitting device, characterized in that: The following steps are involved: A signal receiving module, used for receiving a digital signal sequence S(t), and performing modulation processing on the digital signal sequence S(t) to obtain a digital signal sequence C(t); A noise generating module, configured to generate noise within a preset frequency range, wherein the preset frequency range includes the frequency range of the digital signal sequence S(t); and to process the noise based on a notch filter to obtain a signal N(t); The coupling module is used to couple the digital signal sequence C(t) and the signal N(t) to obtain the signal B(t), and transmit the signal B(t) after radio frequency modulation.

6. The transmitting device according to claim 5, characterized in that: The signal receiving module is also used for: The digital signal sequence S(t) is modulated based on single-frequency FSK to obtain a digital signal sequence C(t).

7. The transmitting device according to claim 6, characterized in that: The noise generating module is also used for: Use the white noise generator to generate noise in a preset frequency range.

8. The transmitting device according to claim 6, characterized in that: The frequency of single-frequency FSK is f, the bandwidth of the digital signal sequence S(t) is b, and the spectrum range of the digital signal sequence C(t) is [fb,f+b].

9. A method for receiving a digital signal sequence, characterized in that: The following steps are involved: A radio frequency signal is received, the radio frequency signal is narrow-band filtered to obtain a signal B′(t), and the signal B′(t) is demodulated and baseband filtered to obtain a signal S′(t); The signal S′(t) is modulated and shaped to obtain a digital signal sequence.

10. A receiving device for a digital signal sequence, characterized in that: Includes the following modules: A first processing module is used to receive a radio frequency signal, perform narrowband filtering on the radio frequency signal to obtain a signal B′(t), and perform demodulation processing and baseband filtering processing on the signal B′(t) to obtain a signal S′(t); The second processing module is used to perform modulation processing and shaping processing on the signal S′(t) to obtain a digital signal sequence.

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