摘要
针对甚小线性调频键控（VMCK）调制的通信系统，研究了接收滤波器的设计。通过对VMCK信号在不同带宽下的功率百分比分析发现，VMCK信号作为一种频谱结构不对称的特殊双边带信号，其接收滤波器不能采用以信号基波频率为中心对称的传统设计方式，提出以最高功率百分比频段的中心点作为滤波器的中心频率，得到最佳的中心频率为1．25倍的基波频率，并对几类滤波器窗函数进行对比，选定了主瓣宽度较窄且第一旁瓣峰值较低的哈明（Hamming）窗。仿真结果表明，在信噪比（SNR）为3dB时，系统误符号率（SER）达到10-3，且信号功率谱密度带外衰减60dB时，频带利用率达到1．74bps／Hz.
Aiming at the communication systems based on very of receiver filter was researched. The research revealed minimum chirp keying （VMCK） modulation, the design that the VMCK modulation signal is a special case of a double sideband signal with an asymmetric spectrum structure, and its receiver filter can not be designed using the conventional design of symmetrical with the fundamental wave. By making an analysis of VMCK power percentage under different bandwidths, the. center of the highest power percentage band as the filter center frequency was pro- posed. As a result, the optimal center frequency of 1.25 times of fundamental frequency was given. The Hamming window with a narrower main lobe width and a lower first side lobe peak was selected by comparison. The simula- tion results showed that when the signal noise ratio （SNR） was 3dB, the symbol error ratio （SER） reached about 10-3. Furthermore, when attenuation of the power spectral density （PSD） for the signal was 60dB, the bandwidth efficiency achieved 1.74bps/Hz.
出处
《高技术通讯》
CAS
CSCD
北大核心
2013年第1期23-28,共6页
Chinese High Technology Letters
基金
国家自然科学基金（61132003,61171086）和上海市重点学科（S30108）资助项目.
