超宽带(UWB)脉冲波形设计不仅要求满足正交性,还要满足UWB系统信号发射所要求的FCC频谱限制.基于B样条良好的性质,利用样条函数逼近原理,提出了一种使用B样条来设计UWB脉冲波形的方法.从B样条产生电路构成的通信系统出发,将波形设计问题转化为有约束的逼近问题求解.该逼近优化问题把频谱利用率作为目标函数,正交性和频谱屏蔽作为约束条件.所以这种方法设计得到的UWB模板信号频谱在符合规定频率特性的同时,还能较大程度地提高频谱利用率,实现电路也简单易行.仿真验证了该方法的可行性和优点.
The Ultra-Wideband (UWB) pulse waveform in communication need not only achieve orthogonality but also meet the Federal Communications Commission(FCC) spectral mask for the UWB commercial system. B-spline functions exhibit good approximation properties when serving as a basis in function learning. In this paper, a flexible UWB pulse waveform design method is proposed based on B- spline basis. The task of UWB pulse waveform design is represented as a constrained optimization problem, which takes the spectrum utility ratio as the target function, and takes orthogonality and spectral mask as the constraint. Subsequently the UWB pulse waveforms obtained in this way have the advantages of better spectrum utility ratio and complying with the FCC spectrum mask. The system of B- spline is also applicable to implemented circuits. Experimental results show the feasibility and merits of the proposed method.