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An Encryption System for Securing Physical Signals

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Part of the Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering book series (LNICST,volume 335)


Secure communication is a necessity. However, encryption is commonly only applied to the upper layers of the protocol stack. This exposes network information to eavesdroppers, including the channel’s type, data rate, protocol, and routing information. This may be solved by encrypting the physical layer, thereby securing all subsequent layers. In order for this method to be practical, the encryption must be quick, preserve bandwidth, and must also deal with the issues of noise mitigation and synchronization.

In this paper, we present the Vernam Physical Signal Cipher (VPSC): a novel cipher which can encrypt the harmonic composition of any analog waveform. The VPSC accomplishes this by applying a modified Vernam cipher to the signal’s frequency magnitudes and phases. This approach is fast and preserves the signal’s bandwidth. In the paper, we offer methods for noise mitigation and synchronization, and evaluate the VPSC over a noisy wireless channel with multi-path propagation interference.


  • Physical channel security
  • Vernam Cipher
  • Harmonic encryption
  • FFT
  • Signal encryption
  • Waveforms

Y. Mirsky—Part of this author’s work was done in the Jerusalem College of Technology.

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  1. 1.

    The Python source code to the VPSC can be found online:

  2. 2.

    The largest magnitude of the system is \(\phi -\varepsilon \) and not phi, similar to how in nmodm, the largest n can be is \(m-1\).

  3. 3.

    The Python source code to the VPSC can be found on online:


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This research was partly funded by the Israel Innovations Authority under WIN - the Israeli consortium for 5G Wireless intelligent networks.

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Correspondence to Yisroel Mirsky .

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10 Appendix - Additional Figures

10 Appendix - Additional Figures

Fig. 10.
figure 10

QAM-16 constellation plots of the deciphered and demodulated symbols (1900 MHz LTE OFDMA), with various types of noise and interference, where red indicated incorrectly demodulated symbols. (Color figure online)

Fig. 11.
figure 11

The RSA method’s failure demonstrated by a sine wave on the top (plaintext) and the encrypted RSA signal on the bottom (ciphertext).

The proof that the Vernam Cipher and OTP can be extended from binary to N-ary values with out loss of secrecy, can be found here:

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Mirsky, Y., Fedidat, B., Haddad, Y. (2020). An Encryption System for Securing Physical Signals. In: Park, N., Sun, K., Foresti, S., Butler, K., Saxena, N. (eds) Security and Privacy in Communication Networks. SecureComm 2020. Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering, vol 335. Springer, Cham.

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