摘要
检波是无线电通信系统接收链路的重要环节,广泛应用在音乐广播、电视图像信号等传输领域。目前应用较多的是包络检波,属于大信号检波,无法对小信号检波,且只能用于普通调幅波解调。调制信号在频率较高时容易产生惰性失真,而且由于低频交流负载与直流负载不一致导致产生负峰切割失真。文中设计了基于MC1496的乘积型同步检波电路,采用单电源供电。实验结果证明,该电路在为芯片内部器件提供合适的静态偏置电流的前提下,能够将输入信号沿频率轴线性搬移,实现普通调幅波及双(单)边带调幅信号的检波,有效减小了检波失真。
Detection plays an important role in receive chain of radio communication systems,and widely used in music broadcasting,television image signal transmission fields.At present envelope detection is mainly used only for ordinary amplitude modulation in condition of large signal,not for weak signal.Inert distortion appears under condition of high frequency amplitude modulation signal and negative peak cutting distortion appears due to the inconsistency between load of DC and load of low frequency AC.A single-power supply synchronous detector circuit achieved by MC1496 is proposed.Test result shows that spectrum linear shifting procedure achieved under condition of providing suitable static bias current for internal devices in chip.And also realize the detection of both ordinary amplitude modulated signal and double(single)side-band modulated signal and effectively reduces the distortion of detection.
作者
李之奇
LI Zhiqi(Department of Information and Control Engineering,Shenyang Institute of Science and Technology,Shenyang 110167,China)
出处
《电子设计工程》
2021年第23期185-189,共5页
Electronic Design Engineering
关键词
同步检波
调幅
频谱搬移
MC1496
synchronous detection
amplitude modulation
spectrum shifting
MC1496
