In response to the growing capacities and various losses in satellite communication, coherent detection has been investigated because of its high sensitivity and spectral efficiency. However, owing to the optical hybrid structure, conventional homodyne coherent detection schemes inherently suffer a 3 dB loss when the modulation order is increased from binary to quadrature or higher. In this paper, a novel coherent detection scheme based on a single balanced detector is proposed. By using the half-symbol rate as the frequency offset of the local oscillator, the OQAM signal was transmitted with an improved signal-to-noise ratio and a simpler structure than those of conventional coherent homodyne QAM detection. Mathematical analyses, simulations, and proof-of-concept experiments were performed on the proposed schemes.