复数乘法

In comparison with traditional pipeline FFT, the complex multiplication was implemented by shifting and addition operations in order to eliminate multiplication unit and coefficient ROM.

与传统的流水线FFT比较，该模块中的复数乘法运算全部采用移位相加操作完成，因而消除了乘法器及旋转因子ROM的使用，降低了功耗。

Signal processing approach presented in this paper based on neural network algorithm (spectral analysis, Random noise filtering) does not involve the complex multiplication and addition operations. Its computing accuracy is high. It is particularly suitable for the implementation of software and hardware based on DSP chip.

所提出的基于神经网络算法的信号处理方法(频谱分析、随机噪声滤波)不涉及复数的乘法运算和复数的加法运算，计算精度高，特别适合基于DSP芯片的软、硬件实现。

to reduce the impact of carrier frequency offset in ofdm system,this thesis designs a new carrier frequency offset estimation scheme for ofdm system.the carrier frequency offset estimation includes acquisition and tracking.we adopt variable step size adaptive algorithm.the acquisition range of the proposed algorithm is as large as one half of the overall signal bandwidth.through this method we can not only avoid the feedback by using forward error correction,but also reduce the times of complex multiplication in order to reduce the power consumption of the system.this algorithm not only has low complexity and fast convergence nut also can improve the demodulation performance of ofdm system.computer simulation illustrates the superior performance of the proposed algorithm with regard to estimation accuracy in both awgn channel and multi—path channel.

摘 要：为了减小正交频分复用系统受频率偏差的影响，在ofdm系统中设计了一种新的载波频偏估计算法。频偏估计包括跟踪和捕获两个阶段，文中采用变步长自适应算法来进行跟踪，这个跟踪算法的捕捉范围是整个信号带宽的一半。通过此方法，不但可以利用前向纠错的方式来避免反馈，而且可以缩减复数乘法的次数以降低计算复杂度和系统功耗。该方法运算复杂度低，并具有较好的收敛性，能改善odfm的解调性能。从计算机的仿真效果可以看出无论是在awgn信道上还是在多径信道上都表现出了卓越的性能。

Definition : plural addition, the plural subtraction, multiplication complex, realistic Ministry for the imaginary part of the plural output, the same judge two plural.

定义方法：复数加法、复数减法、复数乘法、求实部，求虚部，将复数输出，判断两个复数相等。

It is compact in structure, stable and efficient for practical uses with high package density. 7. Based on negative binary coding method, a modified two-dimensional crossed-ring interconnection network and four subarrays outproduct technique, an optoelectronic parallel martix-vector complex multiplication processor is presented.

借助负二进制数字表达、空间编码加权-移位四区域复数外积乘法技术和改进的矩阵-矢量啮合算法，研制了光电混合并行处理的矩阵-矢量乘法器。

This thesis consists of the following: 1. According to transmission line theory and Fick laws, The relation between each circuit element and frequency was given.

全文分： 1。从传输线理论和Fick定律出发，推导出了用于复数非线性最小二乘法模拟的各种电路元件与频率的关系式。

This process needs to be done is to factor the function (-1) ^ multiplied by the input image to achieve the center of filter change, and also requires a real matrix multiplied by a complex matrix by calling the two images of the multiplication process to achieve multiplication of the corresponding elements, calculating the anti-Fourier transform at the same time, the result multiplied by (-1) ^ and check the final calculation of the Department of the spectrum in fact.

这个程序需要完成的功能是用因子（-1）^乘以输入图像以实现滤波的中心变换，并还要求用一个实矩阵乘以一个复数矩阵通过调用两个图像的乘法程序来实现对应元素的相乘，同时计算反傅立叶变换，得到的结果乘以（-1）^并取其实部最后计算频谱。

The modified version has no limitation on the number of bits for encoding the multiplicand and the multiplier, greatly save the space-bandwidth-product, and the mixed digital string can be directly weighted and summed to obtain the final product.

其中二值虚数基编码使复数相乘简化为两次乘法，四值虚数基编码（数基为2j）使复数相乘进一步简化为一次乘法，变得和实数操作一样。

First, orthogonal circle operator was modeled in terms of Zernike orthogonal complex moment; the one-to-one mapping between the edge point and the parameters of the circle was established by the algorithm. Then, quadratic polynomial interpolation was adopted to further locate the edge points in the gradient direction.

首先根据Zernike正交复数矩建立圆物体边缘点与边缘参数之间的映射关系，并提取边缘点；然后利用二次多项式插值在梯度方向上对提取出的边缘点进行进一步定位；最后利用最小二乘法拟合插值后的边缘点，得到亚像素精度的圆参数。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。