We study communication systems over band-limited Additive White Gaussian Noise (AWGN) channels in which the transmitter output is constrained to be symmetric binary (bi-polar). In this work we improve the original Ozarov-Wyner-Ziv (OWZ) lower bound on capacity by introducing a new achievability scheme with two advantages over the studied OWZ scheme which is based on peak-power constrained pulse-amplitude modulation. Our scheme achieves a moderately improved information rate and it does so with much less sign transitions of the binary signal. The gap between the known upper-bound based on spectral constrains of bi-polar signals and our achievable lower bound is reduced to 0.86 bits per Nyquist interval at high SNR.
翻译:我们的研究是通过带状限制的Additive White Gaussian噪音(AWGN)频道的通信系统,在这种频道中,发射机的输出只能是对称的二进制(双极),在这项工作中,我们改进了原Ozarov-Wyner-Ziv(OWZ)的能力约束,采用了一个新的可实现性计划,它比所研究的OWZ计划有两种优势,后者以峰值功率受限的脉冲调制为基础。我们的计划实现了适度改进的信息率,而二进制信号的转换要少得多。基于双极信号的光谱限制而已知的上界与我们可实现的下界之间的差距在高SNR的Nyquist间隔中减少到0.86比特。