An analog microwave signal correlator, based on parametric pumping of a spin wave by a radio frequency (RF) magnetic field, is demonstrated. The binary codes to be correlated modulate the two microwave signals input to the device to, respectively, excite the spin wave and RF field at twice the carrier frequency of the spin wave. The magnetic field parametrically pumps the spin wave, generating a counterpropagating idler spin wave, the modulation of which is the cross-correlation of the binary codes. In the experimental device implemented, correlation of codes up to 16 chips in length at a spin-wave carrier frequency of 1.2 GHz is demonstrated. The code length is limited by the time available for the parametric interaction as well as the signal bandwidth of the device. Process gain, which quantifies the performance of the correlator in recognizing a given code and rejecting interfering codes, is determined for shorter codes and found to be close to the theoretical maximum for each length. The correlator efficiency, with a bilinearity coefficient of –79 dBm, is poor. However, there remains a significant scope for optimization of the experimental device so that correlation of longer codes with improved efficiency will be possible.

中文翻译：

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自旋波参量泵浦二进制编码调制微波信号的相关性

演示了基于射频 (RF) 磁场参数泵浦自旋波的模拟微波信号相关器。要相关的二进制代码调制输入到设备的两个微波信号，分别以两倍于自旋波载波频率的频率激发自旋波和射频场。磁场参数泵浦自旋波，产生反向传播的空闲自旋波，其调制是二进制代码的互相关。在实施的实验装置中，演示了在 1.2 GHz 自旋波载波频率下长达 16 个码片长度的代码相关性。代码长度受限于参数交互可用的时间以及设备的信号带宽。过程增益，量化相关器在识别给定代码和拒绝干扰代码方面的性能，针对较短代码确定并发现接近每个长度的理论最大值。双线性系数为 –79 dBm 的相关器效率很差。然而，实验设备的优化仍有很大的余地，以便将更长的代码与提高的效率相关联将成为可能。