Radio analog telephone communication encryption method, device, equipment and medium

Abstract

The invention discloses a radio analog telephone communication encryption method, device and equipment and a medium, and the method comprises the steps: generating a frequency spectrum segment number and a pseudo-random sorting sequence through a preset encryption algorithm; and carrying out controllable segmentation on the total spectrum of the analog voice according to a continuous sequence from low frequency to high frequency, carrying out sequence recombination on each sub-spectrum according to a pseudo-random sequence, finally combining and outputting encrypted voice, and recovering the original voice by utilizing the same pseudo-random sequence reverse recombination at a receiving end. Therefore, the time-frequency continuity and statistical characteristics of the voice spectrum in the traditional radio analog communication are fundamentally changed. According to the method, frequency spectrums are recombined as a whole according to a pseudo-random rule, so that an eavesdropper can only obtain disordered voice signals after the frequency spectrums are rearranged even if the eavesdropper intercepts the signals, and the difficulty of passive cracking means such as frequency spectrum analysis, filtering reduction and voice recognition is remarkably increased; the problem that in the prior art, radio analog telephone communication is insufficient in encryption and easy to crack is solved.

Description

Technical Field

[0001] This invention relates to the field of encrypted communication technology, and in particular to a method, apparatus, device and medium for encrypting radio analog communication. Background Technology

[0002] In modern communication technology, radio communication occupies an important position due to its wide frequency range and application areas. Radio communication frequencies range from 3Hz to 300GHz, covering many important fields, including military communication, satellite communication, radar communication, and aviation and maritime communication. However, traditional analog radio communication technology has a significant drawback: the lack of effective encryption methods during transmission, resulting in very low security. Existing analog radio communication technology typically modulates the voice signal using analog modulation and then directly mixes it to a designated frequency signal before transmitting it as a radio signal through an antenna. In this process, the signal structure of analog communication is relatively simple, and the demodulation process is also relatively intuitive, making the signal easy to crack. Once the signal is intercepted, attackers can recover the original voice content using simple techniques. Therefore, due to the lack of complex encryption methods, traditional analog radio communication is almost defenseless against malicious attacks. For the above reasons, traditional analog radio communication poses serious security risks in military, government, and commercial fields. The communication content in these fields often involves sensitive information, and once leaked, it could have serious consequences. Therefore, there is an urgent need for an encryption method for analog radio communication to solve the problem of insufficient encryption and susceptibility to cracking in existing technologies. Summary of the Invention

[0003] The embodiments of the present invention provide a method, apparatus, device and medium for encrypting analog radio communication, aiming to solve the problem that the encryption of analog radio communication is insufficient and easily cracked in the prior art.

[0004] In a first aspect, embodiments of the present invention provide a method for encrypting analog radio communication. The method includes: generating a number of spectrum segments and a pseudo-random sorting sequence using a preset encryption algorithm; segmenting the total spectrum of the analog speech signal according to the number of spectrum segments in a continuous order from low frequency to high frequency to obtain a segment set; recombining the sub-spectrums in the segment set according to the pseudo-random sorting sequence; merging the reordered sub-spectrums into an encrypted speech signal and broadcasting it from an output end; and performing reverse spectrum recombining at a receiving end using the same pseudo-random sorting sequence to restore the original speech.

[0005] Secondly, embodiments of the present invention also provide a radio analog voice communication encryption device for performing the radio analog voice communication encryption method described above.

[0006] Thirdly, embodiments of the present invention also provide a computer device, the computer device including a memory and a processor connected to the memory; the memory is used to store a computer program; the processor is used to run the computer program stored in the memory to perform the steps of the above-described radio analog communication encryption method.

[0007] Fourthly, embodiments of the present invention also provide a computer-readable storage medium storing a computer program, the computer program including program instructions, which, when executed by a processor, can implement the steps of the above-described radio analog communication encryption method.

[0008] Compared with the prior art, the beneficial effects of the present invention are:

[0009] In the technical solution of this invention, the radio analog voice communication encryption method generates a number of spectrum segments and a pseudo-random sorting sequence through a preset encryption algorithm. It then controllably segments the total spectrum of the analog voice signal in a continuous order from low to high frequency, reassembles each sub-spectrum according to the pseudo-random sequence, and finally merges and outputs encrypted voice. At the receiving end, the original voice is recovered by reverse reconstruction using the same pseudo-random sequence. This fundamentally changes the original order of the voice signal spectrum in traditional radio analog voice communication, thus achieving voice encryption. This method scatters and reassembles the spectrum as a whole according to pseudo-random rules, ensuring that even if an eavesdropper intercepts the signal, they only receive a chaotic voice signal with the spectrum rearranged. This significantly increases the difficulty of passive cracking methods such as spectrum analysis, filtering and restoration, and voice recognition, solving the problem of insufficient encryption and susceptibility to cracking in existing radio analog voice communication technologies. Attached Figure Description

[0010] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 A flowchart of the radio analog voice communication encryption method provided by the present invention;

[0012] Figure 2 This is a first sub-flowchart of the radio analog voice communication encryption method provided by the present invention;

[0013] Figure 3 This is a sub-flowchart of the second sub-flowchart of the radio analog voice communication encryption method provided by the present invention;

[0014] Figure 4The third sub-flowchart of the radio analog voice communication encryption method provided by the present invention;

[0015] Figure 5 The fourth sub-flowchart of the radio analog voice communication encryption method provided by the present invention;

[0016] Figure 6 The fifth sub-flowchart of the radio analog voice communication encryption method provided by the present invention;

[0017] Figure 7 The sixth sub-flowchart of the radio analog voice communication encryption method provided by the present invention;

[0018] Figure 8 A schematic block diagram of the units of the radio analog voice communication encryption device provided by the present invention;

[0019] Figure 9 A schematic block diagram of a computer device provided in an embodiment of the present invention;

[0020] Figure 10 This is a schematic diagram of the overall spectrum before and after the encryption sub-spectrum position transformation of the radio analog voice communication encryption method provided in the embodiments of the present invention.

[0021] Figure 11 This is a schematic diagram of the segmented encryption process of the radio analog voice communication encryption method provided in an embodiment of the present invention. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0024] It should also be understood that the terminology used in this specification is for the purpose of describing embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0025] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0026] To address the problem of insufficient encryption and susceptibility to cracking in existing analog radio communication technologies, this invention discloses a method for encrypting analog radio communication. This method can be applied to shortwave radios, such as the commercially available shortwave VCR780 product.

[0027] Reference Figures 1 to 7 The method includes the following steps:

[0028] S110. Generate the number of spectrum segments and the pseudo-random sorting sequence using a preset encryption algorithm;

[0029] S120. The total spectrum of the analog speech signal is segmented according to the number of spectrum segments in a continuous order from low frequency to high frequency to obtain a segment set;

[0030] S130. Reassemble the sub-spectrums in the segment set according to the pseudo-random sorting sequence;

[0031] S140. The reordered sub-spectrums are merged into an encrypted voice signal and broadcast from the output end.

[0032] S150. At the receiving end, the same pseudo-random sorting sequence is used to perform reverse spectral order reconstruction to restore the original speech.

[0033] In the radio analog voice communication encryption method of this invention, the AES (Advanced Encryption Standard) encryption algorithm is used to generate the number of spectrum segments and the pseudo-random sorting sequence. First, the number of spectrum segments, n, is determined. According to the AES standard, the key length is 128 bits. It is XORed bitwise with the maximum segment length 0xF until a pseudo-random number in the range of 2-15 is generated, which is the number of voice spectrum segments, n. Then, the 128-bit key is divided into pseudo-random number segments, and the sum of the bits of each segment is the key value of that segment. The number of spectrum segment bits is sorted according to the segment key value to obtain the pseudo-random sorting sequence of the spectrum. For example, refer to... Figure 10 Assuming the encryption sequence generated by the key is [4,3,2,1], then the number of spectrum segments n is 4, and the pseudo-random sorting sequence of the spectrum segments is [4,3,2,1].

[0034] The audio signal spectrum is divided into n parts from low to high frequencies. For example, assuming the audio signal spectrum ranges from 300Hz to 3000Hz, and the number of segments n is 4, then the first part is 300Hz to 750Hz, the second part is 750Hz to 1500Hz, the third part is 1500Hz to 2250Hz, and the fourth part is 2250Hz to 3000Hz. Filters are used to divide the audio signal spectrum into these n parts. Specifically, low-pass filters (LPF), band-pass filters (BPF), and high-pass filters (HPF) can be used to achieve segmentation. For example, a low-pass filter with a cutoff frequency of 750Hz can be used to extract the 300Hz to 750Hz frequency band, a band-pass filter with a passband of 750Hz to 1500Hz can be used to extract the 750Hz to 1500Hz frequency band, and so on.

[0035] Based on the pseudo-random sorting sequence [4,3,2,1] above, rearrange the sub-spectrums. (Refer to...) Figure 11 The specific steps are as follows:

[0036] The first frequency band (300Hz-750Hz) and the fourth frequency band (2250Hz-3000Hz) are swapped;

[0037] The second spectrum segment (750Hz–1500Hz) is swapped with the third spectrum segment (1500Hz–2250Hz).

[0038] The specific methods for achieving spectrum recombination are as follows:

[0039] The first spectrum segment 300Hz to 750Hz is passed through a low-pass filter with a cutoff frequency of 750Hz. The signal is then multiplied with a carrier frequency of 1950Hz to achieve spectrum shifting. The shifted signal is then passed through a high-pass filter with a cutoff frequency of 2250Hz to achieve the shifting of the 300Hz to 750Hz portion of the signal to 2250Hz to 3000Hz.

[0040] The second spectrum segment 750Hz~1500Hz is passed through a bandpass filter with a passband of 750Hz~1500Hz. The signal is then multiplied with a carrier frequency of 750Hz to achieve spectrum shifting. The shifted signal is then passed through a bandpass filter with a passband of 1500Hz~2250Hz to achieve the shifting of the 750Hz~1500Hz part of the signal to 1500Hz~2250Hz.

[0041] After the third spectrum segment 1500Hz~2250Hz is passed through a bandpass filter with a passband of 1500Hz~2250Hz, the signal is multiplied with a carrier frequency of 750Hz to achieve spectrum shifting. The shifted signal is then passed through a bandpass filter with a passband of 750Hz~1500Hz to achieve the shifting of the 1500Hz~2250Hz part of the signal to 750Hz~1500Hz.

[0042] The fourth spectrum segment, 2250Hz to 3000Hz, is passed through a high-pass filter with a cutoff frequency of 2250Hz. The signal is then multiplied with a carrier wave with a frequency of 1950Hz to achieve spectrum shifting. The shifted signal is then passed through a low-pass filter with a cutoff frequency of 750Hz to achieve the shifting of the 2250Hz to 3000Hz portion of the signal to 300Hz to 750Hz.

[0043] Then, the four signals after being moved are added together to complete the swapping of the analog speech spectrum, thereby forming an encrypted speech signal, which is then broadcast from the output end.

[0044] The receiving end uses the same pseudo-random sorting sequence [4,3,2,1] as the transmitting end to perform reverse spectral order reconstruction and recover the original voice signal. Specifically, the received encrypted voice signal is passed through the same filter and carrier multiplication operation to rearrange the spectral bands. For example, the 2250Hz–3000Hz frequency band is passed through a low-pass filter with a cutoff frequency of 750Hz, and then the signal is multiplied with a carrier frequency of 1950Hz to achieve spectrum shifting. The shifted signal is then passed through a high-pass filter with a cutoff frequency of 2250Hz to recover the 300Hz–750Hz frequency band. Through similar operations, the frequency bands are rearranged to finally recover the original voice signal.

[0045] It should be noted that, in addition to the AES algorithm, this invention can also use encryption algorithms such as RSA and ECC for spectrum encryption. Furthermore, it can combine multiple encryption algorithms to further improve the complexity and security of the encryption.

[0046] In one embodiment, reference is made to Figure 2 The steps in S110 include:

[0047] S111. Generate a key using the AES encryption algorithm;

[0048] S112. Perform an XOR operation between the key and a preset fixed value to generate a number of spectrum segments ranging from two to a preset upper limit value, denoted as n;

[0049] S113. Divide the preset number of bits into n segments, calculate the key value of each segment, and the key value of each segment is the sum of the values ​​of all bits in the segment;

[0050] S114. Generate the pseudo-random sorting sequence by sorting the values ​​of each key segment.

[0051] First, a 128-bit initial key is generated using the AES algorithm. This key will be used to generate the number of spectrum segments and the pseudo-random sorting sequence. Then, a pre-defined fixed value, such as 15, is chosen. The choice of this fixed value should ensure that the final number of spectrum segments, n, is within a reasonable range, i.e., between 2 and 15. The generated 128-bit key is then XORed with the fixed value of 15. Specifically, each bit of the key is XORed with each bit of the fixed value to generate a new 128-bit binary number. This generated 128-bit binary number is converted to a decimal number, which is the number of spectrum segments, n. If the generated decimal number is not within the range of 2 to 15, it can be adjusted to this range using a modulo operation. For example, if the generated decimal number is 16, it is modulo 14 and then 2 is added.

[0052] Next, the 128-bit key is divided into n segments. For example, assuming the number of spectrum segments n is 4, the 128-bit key is divided into four 32-bit segments. Then, all bits within each segment are summed to obtain the key value for each segment. The above steps are repeated to calculate the key value for all segments.

[0053] Finally, the calculated key values ​​for each segment are sorted to generate a pseudo-random sorting sequence. For example, assuming the key values ​​for the four segments are 16, 15, 14, and 13, sorting them from largest to smallest yields a pseudo-random sorting sequence of [4, 3, 2, 1]. This pseudo-random sorting sequence will be used for subsequent spectrum segmentation and recombination operations to ensure the randomness and security of the encryption process. Through the above steps, this embodiment generates the number of spectrum segments and the pseudo-random sorting sequence using the AES encryption algorithm, ensuring a high level of security and reliability in the encryption process of analog radio communication.

[0054] In one embodiment, reference is made to Figure 3 Step S120 includes:

[0055] S121. The lowest frequency sub-band in the total spectrum is extracted by a low-pass filter, and its cutoff frequency is the first segmentation frequency.

[0056] S122. The highest frequency sub-band in the total spectrum is extracted by a high-pass filter, and its cutoff frequency is the (n-1)th segment frequency.

[0057] S123. The intermediate sub-frequency bands are successively extracted through n-2 bandpass filters. The passband range of the k-th bandpass filter is from the k-th segmented frequency to the (k+1)-th segmented frequency, and the passband boundaries of adjacent bandpass filters are continuously connected.

[0058] First, determine the frequency range of the total spectrum. (Refer to...) Figure 11 Assume the total frequency spectrum range is 300Hz to 3000Hz, and the number of frequency segments n is 4. Select a low-pass filter (LPF) with a cutoff frequency of 750Hz as the first segment frequency. Pass the analog speech signal through this low-pass filter, extracting a sub-band from 300Hz to 750Hz. Specifically, the low-pass filter will filter out frequency components above 750Hz, retaining the frequency band from 300Hz to 750Hz.

[0059] Then, a high-pass filter (HPF) with a cutoff frequency of 2250Hz is selected. The analog speech signal is passed through this high-pass filter, and a sub-band from 2250Hz to 3000Hz is extracted. Specifically, the high-pass filter will filter out frequency components below 2250Hz, retaining the frequency band from 2250Hz to 3000Hz.

[0060] Finally, assuming the number of spectral segments, n, is 4, two bandpass filters (BPFs) are needed to extract the two middle sub-bands. Specifically, the first BPF has a passband range of 750Hz to 1500Hz. Passing the analog speech signal through this BPF extracts the 750Hz to 1500Hz sub-band. That is, this BPF filters out frequency components below 750Hz and above 1500Hz, retaining the 750Hz to 1500Hz band. The second BPF has a passband range of 1500Hz to 2250Hz. Passing the analog speech signal through this BPF extracts the 1500Hz to 2250Hz sub-band. That is, this BPF filters out frequency components below 1500Hz and above 2250Hz, retaining the 1500Hz to 2250Hz band.

[0061] Through the steps described above, this embodiment segments the total spectrum of the analog voice signal using low-pass, high-pass, and band-pass filters, ensuring that the frequency range of each sub-band is accurate and continuous. This segmentation method not only improves the accuracy of spectrum division but also provides a foundation for subsequent spectrum reassembly and encryption, ensuring a high degree of security and reliability in the encryption process of analog radio communication.

[0062] In one embodiment, reference is made to Figure 4 The steps in S130 include:

[0063] S131. Determine the target frequency band position corresponding to each sub-spectrum based on the pseudo-random sorting sequence;

[0064] S132. Generate a carrier signal frequency based on the difference between the center frequency of the sub-spectrum and the center frequency of the target frequency band position;

[0065] S133. Multiply the sub-spectrum with the carrier signal to shift the spectrum segment to the target frequency band position, and extract the shifted signal through the filter corresponding to the target frequency band to generate the reconstructed sub-spectrum signal.

[0066] The target frequency band position of each sub-spectrum is determined based on the generated pseudo-random sorting sequence. Assuming the pseudo-random sorting sequence is [4,3,2,1], then the target position of the first sub-spectrum (300Hz~750Hz) is the fourth frequency band (2250Hz~3000Hz), the target position of the second sub-spectrum (750Hz~1500Hz) is the third frequency band (1500Hz~2250Hz), the target position of the third sub-spectrum (1500Hz~2250Hz) is the second frequency band (750Hz~1500Hz), and the target position of the fourth sub-spectrum (2250Hz~3000Hz) is the first frequency band (300Hz~750Hz).

[0067] The center frequency difference between the center frequency of each sub-spectrum and the center frequency of the target frequency band is calculated to generate the corresponding carrier signal frequency. For example, the center frequency of the first sub-spectrum (300Hz–750Hz) is 525Hz, and the center frequency of the target frequency band (2250Hz–3000Hz) is 2625Hz, with a center frequency difference of 2100Hz. Therefore, the generated carrier signal frequency is 2100Hz. Similarly, the center frequency of the second sub-spectrum (750Hz–1500Hz) is 1125Hz, and the center frequency of the target frequency band (1500Hz–2250Hz) is 1875Hz, with a center frequency difference of 750Hz. Therefore, the generated carrier signal frequency is 750Hz. The center frequency of the third sub-spectrum (1500Hz–2250Hz) is 1875Hz, and the center frequency of the target frequency band (750Hz–1500Hz) is 1125Hz, with a center frequency difference of 750Hz. Therefore, the generated carrier signal frequency is 750Hz. The center frequency of the fourth sub-spectrum (2250Hz~3000Hz) is 2625Hz, and the center frequency of the target frequency band (300Hz~750Hz) is 525Hz, with a center frequency difference of 2100Hz. Therefore, the generated carrier signal frequency is 2100Hz.

[0068] Each sub-spectrum is multiplied by its corresponding carrier signal to shift the spectrum. For example, multiplying the first sub-spectrum (300Hz–750Hz) by a 2100Hz carrier signal shifts this spectrum to 2250Hz–3000Hz. Then, the shifted signal is extracted using a high-pass filter with a cutoff frequency of 2250Hz to generate the reconstructed sub-spectrum signal. The second sub-spectrum (750Hz–1500Hz) is multiplied by a 750Hz carrier signal, shifting this spectrum to 1500Hz–2250Hz. Then, the shifted signal is extracted using a bandpass filter with a passband of 1500Hz–2250Hz to generate the reconstructed sub-spectrum signal. The third sub-spectrum (1500Hz–2250Hz) is multiplied by a 750Hz carrier signal, shifting this spectrum to 750Hz–1500Hz. Then, the shifted signal is extracted through a bandpass filter with a passband of 750Hz to 1500Hz to generate the recombined sub-spectrum signal. The fourth sub-spectrum (2250Hz to 3000Hz) is multiplied by the -2100Hz carrier signal to shift this spectrum band to 300Hz to 750Hz. Then, the shifted signal is extracted through a low-pass filter with a cutoff frequency of 750Hz to generate the recombined sub-spectrum signal.

[0069] Through the above steps, this embodiment reassembles the sub-spectrums in the segment set according to the pseudo-random sorting sequence, ensuring that each sub-spectrum is accurately moved to the target frequency band position.

[0070] In one embodiment, reference is made to Figure 5 The steps in S140 include:

[0071] S141. Combine and add the n recombined sub-spectral signals to obtain the encrypted voice signal;

[0072] S142. The encrypted voice signal is broadcast from the output terminal after gain compensation, wherein the gain value of the gain compensation is n.

[0073] After spectrum recombination, the n recombined sub-spectral signals are merged and added together to generate an encrypted voice signal. Assume the number of spectrum segments n is 4, and the recombined sub-spectral signals are voice1_mod_filter, voice2_mod_filter, voice3_mod_filter, and voice4_mod_filter. Specifically, the four recombined sub-spectral signals are added together to obtain the encrypted voice signal. The mathematical expression is:

[0074] voice_mod=2×(voice1_mod_filter+voice2_mod_filter

[0075] +voice3_mod_filter+voice4_mod_filter)

[0076] Through the above steps, the sub-spectrum signals are merged into a complete encrypted voice signal, ensuring that the signals of all frequency bands are correctly aligned and synthesized.

[0077] During spectrum recombination, the sub-spectral signals are shifted and filtered, which may lead to signal strength loss. Therefore, gain compensation is needed for the encrypted voice signal to restore its original strength. Gain compensation is applied to the merged encrypted voice signal, with a gain value of n. Assuming the number of spectrum segments n is 4, the gain value is 4. The mathematical expression is:

[0078] voice_mod_compensated=4×voice_mod

[0079] Through the above steps, gain compensation is performed on the encrypted voice signal to ensure that the signal strength is consistent with the original signal, thereby guaranteeing the quality of the output signal.

[0080] The gain-compensated encrypted voice signal is then played from the output. Specifically, the voice_mod_compensated signal is output to the output port of a speaker or communication device to complete the playback of the encrypted voice signal.

[0081] In summary, this embodiment combines the reordered sub-spectrums into an encrypted voice signal, performs gain compensation, and then broadcasts it from the output, ensuring high accuracy and reliability in the encryption process of analog radio communication. This merging and gain compensation method not only improves signal integrity but also ensures the quality and strength of the output signal.

[0082] In one embodiment, reference is made to Figure 6 The steps of S150 include:

[0083] S151. At the receiving end, the same pseudo-random sorting sequence is generated using the same key.

[0084] S152. Perform reverse carrier shifting operation according to the spectrum exchange sequence of the encryption process at the output end;

[0085] S153. The merged and restored spectrum segment is output as the original voice through the audio playback device of the receiving end.

[0086] At the receiving end, the same 128-bit key as at the sending end is used. An XOR operation is performed using the AES encryption algorithm and the same fixed value to generate the same number of spectral segments *n* and a pseudo-random sorting sequence. Specifically, the target position for the first sub-spectrum (2250Hz–3000Hz) is 300Hz–750Hz. A carrier signal with a frequency of 2100Hz is generated, and the sub-spectrum is multiplied by the 2100Hz carrier signal to shift it to 300Hz–750Hz. Then, the shifted signal is extracted using a low-pass filter with a cutoff frequency of 750Hz to generate the restored sub-spectrum signal. The target position for the second sub-spectrum (1500Hz–2250Hz) is 750Hz–1500Hz. A carrier signal with a frequency of 750Hz is generated, and the sub-spectrum is multiplied by the 750Hz carrier signal to shift it to 750Hz–1500Hz. Then, the shifted signal is extracted using a bandpass filter with a passband of 750Hz–1500Hz to generate the restored sub-spectrum signal. The target position for the third sub-spectrum (750Hz–1500Hz) is 1500Hz–2250Hz. A carrier signal with a frequency of 750Hz is generated, and this sub-spectrum is multiplied by the 750Hz carrier signal to shift it to the 1500Hz–2250Hz range. Then, the shifted signal is extracted using a bandpass filter with a passband of 1500Hz–2250Hz to generate the restored sub-spectrum signal. The target position for the fourth sub-spectrum (300Hz–750Hz) is 2250Hz–3000Hz. A carrier signal with a frequency of 2100Hz is generated, and this sub-spectrum is multiplied by the 2100Hz carrier signal to shift it to the 2250Hz–3000Hz range. Then, the shifted signal is extracted using a high-pass filter with a cutoff frequency of 2250Hz to generate the restored sub-spectrum signal.

[0087] The four restored sub-spectral signals are combined and added together to generate the restored original speech signal. Specifically, the four restored sub-spectral signals are added together to obtain the original speech signal. The mathematical expression is:

[0088] voice_original

[0089] =voice1_original_filter+voice2_original_filter

[0090] +voice3_original_filter+voice4_original_filter

[0091] The merged original audio signal is then output through the audio playback device at the receiving end. Specifically, the voice_original signal is output to the audio output port of a speaker or communication device to complete the playback of the original audio.

[0092] This embodiment uses the same pseudo-random sorting sequence at the receiving end to perform reverse spectral order reconstruction, recovering the entire process of the original speech. This ensures high accuracy and reliability in the decryption process of analog radio communication. This reverse spectral reconstruction method not only improves the signal recovery quality but also ensures the integrity and security of communication.

[0093] In one embodiment, reference is made to Figure 7 The steps of the radio analog voice communication encryption method also include:

[0094] S160. Real-time monitoring of the energy value of encrypted voice signals. When the energy value is continuously detected to be lower than the preset energy threshold for a first preset duration, it is determined to enter the voice silence segment.

[0095] S170. If the silence state is maintained for more than the second preset duration during the voice silence segment, a preset AES key update command is triggered.

[0096] S180. Synchronize the new key from the output end to the receiving end through in-band signaling, and enable the new key at both the output end and the receiving end at the end of the voice silence segment.

[0097] At the output end, the energy value of the encrypted voice signal is monitored in real time. The energy value can be obtained by calculating the instantaneous power or the square of the amplitude of the signal. Specifically, an energy detector is used to calculate the instantaneous energy value of the encrypted voice signal in real time. A preset energy threshold is set, the energy value of the encrypted voice signal is continuously detected, and the time that it remains below the preset energy threshold is recorded.

[0098] When the energy value of the encrypted voice signal is continuously detected to be lower than a preset energy threshold for a first preset duration, it is determined that the voice silence segment has been entered. For example, if the first preset duration is set to 1 second, when the detected energy value is continuously lower than the preset energy threshold for 1 second, it is determined that the voice silence segment has been entered. At this time, the time point of entering the voice silence segment is recorded, and a timer is started.

[0099] After determining that a voice silence segment has been entered, the energy value of the encrypted voice signal continues to be monitored. If the silence persists for more than a second preset duration within the voice silence segment, a preset AES key update command is triggered. For example, the second preset duration is set to 5 seconds. A new AES key is generated, and preparations are made to synchronize the new key to the receiving end via in-band signaling.

[0100] When an AES key update command is triggered, the new key is synchronized from the output end to the receiving end via in-band signaling. Specifically, for example, a new 128-bit AES key is generated and then sent from the output end to the receiving end via in-band signaling. At the receiving end, the in-band signaling is parsed to obtain and store the new key. At this point, the end time of the voice silence segment is monitored, and the new key is synchronously activated when the voice silence segment ends. Both the output end and the receiving end simultaneously apply the new key to the AES encryption algorithm, ensuring the synchronicity and consistency of the encryption and decryption processes.

[0101] This embodiment determines silent segments by monitoring the energy value of the encrypted voice signal in real time and updates the AES key during the entire process of these silent segments, ensuring a high level of security and reliability in the encryption process of analog radio communication. This key update mechanism not only improves communication security but also ensures dynamic updates and synchronization of the key, preventing it from being cracked due to prolonged use.

[0102] This invention significantly improves the security of analog radio communication through spectrum segmentation and pseudo-random sorting techniques. Its applications are wide-ranging, playing a vital role in applications ranging from military communications, government and public safety, to commercial communications, aviation and maritime communications, and personal communications.

[0103] Figure 8 This is a schematic block diagram of a radio analog voice communication encryption device 600 provided in an embodiment of the present invention. Figure 8 As shown, corresponding to the above-described radio analog communication encryption method, the present invention also provides a radio analog communication encryption device 600. This radio analog communication encryption device 600 includes a unit for performing the above-described radio analog communication encryption method, and the device can be configured in a desktop computer, tablet computer, smartphone, or other terminal.

[0104] Specifically, please refer to Figure 8 The radio analog communication encryption device 600 includes:

[0105] The encryption baseline generation unit 610 is used to generate the number of spectrum segments and the pseudo-random sorting sequence through a preset encryption algorithm;

[0106] Segmentation unit 620 is used to segment the total spectrum of the analog speech signal according to the number of spectrum segments in a continuous order from low frequency to high frequency to obtain a segment set;

[0107] The sequence recombination unit 630 is used to recombine the sub-spectrums in the segment set according to the pseudo-random sorting sequence;

[0108] The merging and transmitting unit 640 is used to merge the reordered sub-spectrums into an encrypted voice signal and broadcast it from the output end.

[0109] The reverse decryption unit 650 is used by the receiving end to perform reverse spectral order reconstruction using the same pseudo-random sorting sequence to restore the original speech.

[0110] In one embodiment, the encryption baseline generation unit 610 includes:

[0111] A periodic acquisition unit is used to generate the number of spectrum segments and a pseudo-random sorting sequence through a preset encryption algorithm;

[0112] A key generation unit is used to generate keys using the AES encryption algorithm.

[0113] The spectrum segment number generation unit is used to perform an XOR operation between the key and a preset fixed value to generate a spectrum segment number, denoted as n, that is between two and a preset upper limit value.

[0114] A key value calculation unit is used to divide the preset number of bits into n segments, calculate the key value of each segment, and the key value of each segment is the sum of the values ​​of all bits in the segment;

[0115] A pseudo-random sorting sequence generation unit is used to generate the pseudo-random sorting sequence by sorting according to the size of each segment of key value.

[0116] In one embodiment, the segmentation unit 620 includes:

[0117] A low-pass segmentation unit is used to extract the lowest frequency sub-band in the total spectrum through a low-pass filter, and its cutoff frequency is the first segmentation frequency.

[0118] The high-pass segmentation unit is used to extract the highest frequency sub-band from the total spectrum through a high-pass filter, and its cutoff frequency is the (n-1)th segmentation frequency.

[0119] A bandpass segmentation unit is used to sequentially extract the middle sub-frequency band through n-2 bandpass filters. The passband range of the k-th bandpass filter is from the k-th segmentation frequency to the (k+1)-th segmentation frequency, and the passband boundaries of adjacent bandpass filters are continuously connected.

[0120] In one embodiment, the sequence recombination unit 630 includes:

[0121] The target frequency band location determination unit is used to determine the target frequency band location corresponding to each sub-spectrum based on the pseudo-random sorting sequence.

[0122] A carrier signal frequency generation unit is used to generate a carrier signal frequency based on the difference between the center frequency of the sub-spectrum and the center frequency of the target frequency band position.

[0123] The sub-spectrum signal reassembly unit is used to multiply the sub-spectrum with the carrier signal to shift the spectrum segment to the target frequency band position, and extract the shifted signal through the filter corresponding to the target frequency band to generate the reassembled sub-spectrum signal.

[0124] In one embodiment, the sequence recombination unit 640 includes:

[0125] The merging and adding unit is used to merge and add the n recombined sub-spectrum signals into the encrypted voice signal;

[0126] A broadcasting unit is used to broadcast the encrypted voice signal from the output terminal after gain compensation, wherein the gain value of the gain compensation is n.

[0127] In one embodiment, the sequence recombination unit 650 includes:

[0128] A receiver sequence generation unit is used to generate the same pseudo-random sorted sequence using the same key at the receiver end.

[0129] The reverse carrier shifting unit is used to perform the reverse carrier shifting operation according to the spectrum exchange sequence of the encryption process at the output terminal;

[0130] The restoration and conversion unit is used to output the merged and restored spectrum segment as the original speech through the audio playback device of the receiving end.

[0131] In one embodiment, the radio analog communication encryption device 600 further includes:

[0132] The voice silence determination unit is used to monitor the energy value of the encrypted voice signal in real time. When the energy value is continuously detected to be lower than the preset capacity threshold for a first preset duration, it determines that the voice silence segment has been entered.

[0133] A timing unit is used to trigger a preset AES key update command when the voice silence state is maintained for more than a second preset duration during the voice silence segment.

[0134] A key replacement unit is used to synchronize a new key from the output end to the receiving end via in-band signaling, and to enable the new key simultaneously at the end of the voice silence segment.

[0135] The aforementioned radio analog communication encryption device 600 can be implemented as a computer program, which can, for example... Figure 9 It runs on the computer device shown.

[0136] Please see Figure 9 , Figure 9This is a schematic block diagram of a computer device 500 provided in an embodiment of this application. The computer device 500 can be a terminal or a server. The terminal can be an electronic device with communication functions, such as a desktop computer, tablet computer, or smartphone. The server can be a standalone server or a server cluster composed of multiple servers.

[0137] See Figure 9 The computer device 500 includes a processor 502, a memory, and a network interface 505 connected via a system bus 501. The memory may include a non-volatile storage medium 503 and internal memory 504.

[0138] The non-volatile storage medium 503 may store an operating system 5031 and a computer program 5032. The computer program 5032 includes program instructions that, when executed, cause the processor 502 to perform a radio analog communication encryption method.

[0139] The processor 502 provides computing and control capabilities to support the operation of the entire computer device 500.

[0140] The internal memory 504 provides an environment for the operation of the computer program 5032 in the non-volatile storage medium 503. When the computer program 5032 is executed by the processor 502, the processor 502 can execute a radio analog communication encryption method.

[0141] This network interface 505 is used for network communication with other devices. Those skilled in the art will understand that... Figure 9 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device 500 to which the present application is applied. The specific computer device 500 may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0142] The processor 502 is used to run a computer program 5032 stored in a memory to implement the steps of the above method.

[0143] It should be understood that in the embodiments of this application, the processor 502 may be a central processing unit (CPU), or it may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0144] It will be understood by those skilled in the art that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program includes program instructions and can be stored in a storage medium, which is a computer-readable storage medium. The program instructions are executed by at least one processor in the computer system to implement the process steps of the embodiments of the above methods.

[0145] Therefore, the present invention also provides a storage medium. This storage medium can be a computer-readable storage medium. The storage medium stores a computer program, wherein the computer program includes program instructions. When executed by a processor, the program instructions cause the processor to perform the steps of the above-described method.

[0146] The storage medium can be any computer-readable storage medium capable of storing program code, such as a USB flash drive, portable hard drive, read-only memory (ROM), magnetic disk, or optical disk.

[0147] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0148] In the several embodiments provided by this invention, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For example, the division of each unit is only a logical functional division, and there may be other division methods in actual implementation. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed.

[0149] The steps in the method of this invention can be adjusted, merged, or reduced in order according to actual needs. The units in the device of this invention can be merged, divided, or reduced according to actual needs. Furthermore, the functional units in the various embodiments of this invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0150] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, a terminal, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention.

[0151] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for encrypting analog radio communication, characterized in that, The method includes: The spectrum segment number and pseudo-random sorting sequence are generated using a preset encryption algorithm; The total spectrum of the analog speech signal is segmented according to the number of spectrum segments in a continuous order from low frequency to high frequency to obtain a segment set; Based on the pseudo-random sorting sequence, the sub-spectrums in the segment set are reassembled. The reordered sub-spectrums are combined into an encrypted voice signal and broadcast from the output. At the receiving end, the same pseudo-random sorting sequence is used to perform reverse spectral order reconstruction to restore the original speech.

2. The radio analog voice communication encryption method according to claim 1, characterized in that, The steps of generating the number of spectrum segments and the pseudo-random sorting sequence using a preset encryption algorithm include: Generate a key using the AES encryption algorithm; The key is XORed with a pre-set fixed value to generate a number of spectrum segments ranging from two to a preset upper limit value, denoted as n. Divide the preset number of bits into n segments, calculate the key value for each segment, and the key value for each segment is the sum of the values ​​of all bits in the segment; The pseudo-random sorting sequence is generated by sorting the values ​​of each key segment according to their size.

3. The radio analog voice communication encryption method according to claim 2, characterized in that, The step of segmenting the total spectrum of the analog speech signal according to the number of spectrum segments in a continuous order from low frequency to high frequency includes: The lowest frequency sub-band in the total spectrum is extracted by a low-pass filter, and its cutoff frequency is the first segmentation frequency. The highest frequency sub-band in the total spectrum is extracted by using a high-pass filter, and its cutoff frequency is the (n-1)th segment frequency. The intermediate sub-frequency bands are successively extracted by n-2 bandpass filters. The passband range of the k-th bandpass filter is from the k-th segmented frequency to the (k+1)-th segmented frequency, and the passband boundaries of adjacent bandpass filters are continuously connected.

4. The radio analog voice communication encryption method according to claim 3, characterized in that, The step of recombining the sub-spectrums in the segment set according to the pseudo-random sorting sequence further includes: Based on the pseudo-random sorting sequence, determine the target frequency band position corresponding to each sub-spectrum; Based on the difference between the center frequency of the sub-spectrum and the center frequency of the target frequency band, a carrier signal frequency is generated. The sub-spectrum is multiplied by the carrier signal to shift the spectrum segment to the target frequency band position, and the shifted signal is extracted by the filter corresponding to the target frequency band to generate the reconstructed sub-spectrum signal.

5. The radio analog voice communication encryption method according to claim 4, characterized in that, The step of merging the reordered sub-spectrums into an encrypted voice signal and broadcasting it from the output includes: The n-channel recombined sub-spectrum signals are combined and added together to form the encrypted voice signal; The encrypted voice signal is broadcast from the output terminal after gain compensation, wherein the gain value of the gain compensation is n.

6. The radio analog voice communication encryption method according to claim 2, characterized in that, The step of performing reverse spectral order reconstruction at the receiving end using the same pseudo-random sorting sequence to recover the original speech includes: At the receiving end, the same pseudo-random sorting sequence is generated using the same key; Perform the reverse carrier shifting operation according to the spectrum exchange sequence of the encryption process at the output end; The merged and restored spectrum bands are output as the original speech through the audio playback device of the receiving end.

7. The radio analog voice communication encryption method according to claim 2, characterized in that, The method further includes: The system monitors the energy value of encrypted voice signals in real time. When the energy value is continuously detected to be lower than the preset energy threshold for a first preset duration, it determines that the system has entered a voice silence segment. If the voice silence lasts for more than a second preset duration during the silence period, a preset AES key update command is triggered. The new key is synchronized from the output end to the receiving end via in-band signaling, and the output end and the receiving end are enabled simultaneously with the new key at the end of the voice silence segment.

8. A radio analog voice communication encryption device, characterized in that, Used to perform the radio analog voice communication encryption method as described in any one of claims 1 to 7.

9. A computer device, characterized in that, The computer device includes a memory and a processor connected to the memory; the memory is used to store a computer program; the processor is used to run the computer program stored in the memory to perform the steps of the method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The storage medium stores a computer program, which includes program instructions that, when executed by a processor, can implement the steps of the method as described in any one of claims 1 to 7.

Images