We consider communication between a legitimate transmitter and a legitimate receiver in the presence of an eavesdropper in the conventional Gaussian wiretap channel setting. Based on Wyner's coding scheme, we show that a code construction using orthogonal codewords can achieve the secrecy capacity of the Gaussian wiretap channel in the wideband regime. This is illustrated through analysis of the error probability between the legitimate parties and the eavesdropper equivocation rate, as well as various simulation results.

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