Quantum Circuit for Coding Acceleration Under Random Disturbance: Case for OFDM Pilot Anti-Denial
Dongyang Xu · 2021
A hidden security issue in OFDM based wireless communications system is the denial of OFDM pilots by spoofing/jamming/nulling regular pilot tones on time-frequency resource grids (TFRG), which cause denial of service (DoS). Lots of literatures have elaborated on solving this problem efficiently by coding on time-frequency domain, but ignored the huge decoding overheads caused by unknown disturbance from attacker. We in this paper discover an interesting fact: the decoding process of information coding that captures signal features can be accelerated doubly under random disturbance by a quantum circuit that exploit quantum phase kick-back. Firstly and most importantly, we show how to formulate the decoding process as a black-box model which can be resolved by a well-designed quantum circuit with two distinguishable quantum states as its inputs. Then we model the searching process of desirable codewords as decision making of the phase information of two quantum state inputs. By employing the quantum phase kick back, we finally prove that one measurement of output of the quantum circuit is enabled to reflect the global information of two inputs and the searching complexity of codewords can be reduced by half under random disturbance.