一种相位差连续可调的双相信号发生器

A Novel Dual Tunable Phase Difference Signal Generator

针对采用移相网络来调节双路输出的相位的不足,以微控制器MSP430F135为主控电路,根据直接接数字频率合成技术(DDFS)的原理,设计了一款相位连续可调的双相、任意波形的信号发生器的硬、软件系统,针对传统计算相位控制字存在的计算量大、频率设定效率低、占用存储空间大或设定频率有误差累积效应等缺点,研制了一种新的计算相位控制字的算法,该方法不需计算大量数据、不需大量存储空间且可显著减低误差的累积效应;以相位累加器位数为28,步距t为0.01为例,采用新算法时,输出相位差的绝对误差最大为1.54×10-6度;利用该算法设计信号发生器既能保持传统任意波形信号发生器的优良性能,又能准确调节两路信号的相位差。

To address the shortcomings of adjusting the phase dual output with phase-- shifting network, taking MSP 430F135 micro- controller as main control circuit and basing on the principle of direct digital frequency synthesis （DDFS）, the hardware and software system of a novel dual tunable phase difference signal generator of arbitrary waveform are designed. To solve the drawbacks of large computation, low efficiency of frequency setting, more storage space occupied or significant cumulative errors of frequency setting when calculating phase control word with traditional methods, a novel calculation way for phase control word is researched. This new method does not need large computation and more space and simulta- neously it can decrease the error greatly. The signal generator with this new method can both maintain the fine performance of the traditional arbitrary waveform signal generator, but also accurately adjust the ohase difference between two signals.