根据快速滤波器组所具有的级联结构、良好频率选择性以及低复杂度的特点,提出了一种多通道同步接收机的设计方法来并行处理多路接收信号.该方法将最小化系统所需乘法器的总数量作为目标函数,以通带和阻带所允许的纹波作为约束条件,设计各级原型滤波器的脉冲响应系数,以满足接收机各通道全局设计指标的要求.以工作频率为88~108 MHz的调频广播信号并行解调系统作为仿真和实验平台对该方法进行验证.结果表明,所提出的设计方法能够满足多通道同步信号处理的要求,且每个通道所需乘法器的数量大约为加权重叠(WOLA)滤波器组方法所需乘法器数量的66.4%,具有较低的实现复杂度.
A scheme to design a simultaneous multichannel receiver is proposed to process multichannel signals in parallel, which is achieved by exploiting the attractive characteristics of a fast filter bank( FFB), such as cascaded structure, high frequency selectivity and lowcomputational complexity. Based on the minimization of the objective function, quantified in terms of the total number of multiplications required, subject to prescribed allowable ripples in the passband and stopband, the impulse response coefficients of the prototype filter in each stage are obtained to meet the requirements of the overall specifications for each channel at the receiver side. Simulations and experimental results on the frequency modulation( FM) broadcast mutlichannel signal receiving system with the FM range from88 to 108 MHz, built upon the proposed FFB structure, are performed to verify its performance. Those results indicate that the proposed scheme is efficient in FM audio indexing applications and has a lower computational complexity, which is approximately 66. 4% of the weighted overlap and add( WOLA) filter banks based solution.