In this paper, design of quantum convolutional codes and their encoder architectures have been investigated We claim that rate-1/(n + 1) quantum systematic convolutional codes can be constructed from rate-1/n classical nonsystematic convolutional codes, where n is greater than or equal to 2. The free distances (dfiee) of proposed rate-1/(n + 1) quantum systematic convolutional codes are larger than that of original rate-1/n classical nonsystematic convolutional codes. A quantum convolutional code encoder can be implemented by using quantum linear feed-forward shift registers and quantum exclusive-OR (controlled-NOT: CNOT) gates. A quantum memory may be used as a quantum state delay element of a quantum register. It is also shown that different encoder architectures are needed for quantum non-superposition and superposition state inputs. For quantum superposition state input, additional Hadamard gates should be used in conjunction with a quantum convolutional code encoder for quantum non-superposition state input.
|Original language||English (US)|
|Number of pages||5|
|Journal||Conference Record - Asilomar Conference on Signals, Systems and Computers|
|State||Published - 2004|
|Event||Conference Record of the Thirty-Eighth Asilomar Conference on Signals, Systems and Computers - Pacific Grove, CA, United States|
Duration: Nov 7 2004 → Nov 10 2004