毕业设计说明书（论文）中文摘要数控振荡器NCO因具有频率精度高、转换时间短、频谱纯度高以及频率相位易编程等特点，而被广泛应用于软件无线电数字上、下变频以及各种频率和相位数字调制解调系统中。 NCO是正交数字混频器的核心部分，它具有频率分辨率高、频率变化速度快、相位可连续线性变化和生成的正弦P余弦信号正交特性好等特点。目前的 FPGA 具有许多乘法器和加法器。然而各种各样的通信技术和矩阵算法则需要三角函数、平方根等的运算。可以使用查找表,或是迭代法。 CORDIC算法;这是一个“移位相加”算法,允许计算不同的三角函数。用CORDIC算法来设计NCO。 基于 CORDIC(坐标旋转数字计算)算法的 NCO(数控振荡器)设计方法克服了传统数字下变频器查询表大的缺点,摆脱了用查表法产生离散正弦信号需要占用大量ROM资源的弊端,提高了资源的利用率,减小了硬件设计的代价。该算法使数控本振和数字混频两个功能合在一起完成,省去了 2个乘法器,利用CORDIC 算法CORDIC旋转的移位-相加流水结构,实现了数字下变频器的设计,其有效性通过仿真得到验证。6489
关键字 数控振荡器 CORDIC算法 串口传输 显示模块 FPGA   
毕业设计说明书（论文）外文摘要
Title        A  NUMERICALLY CONTROLLED OSCILLATOR BASED ON CORDIC ALGORITHM
Abstract
Numerically controlled oscillator with frequency of NCO high precision,
short conversion time of high purity of frequency spectrum and frequency
phase easy programming features, and is widely used in software radio
digital down conversion on, as well as various frequency and phase in a
digital modulation and demodulation system. NCO is a digital quadrature
mixer core part, it has high frequency resolution, frequency change speed,
phase continuous linear change and generates sine P cosine signal
orthogonal properties etc The FPGA has a lot of multiplier and adder.
However, a variety of communications technology and matrix algorithms need
trigonometric functions, square root calculation. You can use a lookup
table, or iterative method. CORDIC algorithm; this is a" shift combined"
algorithm, allows the calculation of different trigonometric function.
CORDIC algorithm is used to design NCO.Based on the CORDIC ( coordinate
rotation digital computing ) algorithm and NCO ( DCO ) design method
overcomes the traditional digital down converter query table big
shortcoming, get rid of the look up table method used to produce discrete
sine signal takes a lot of disadvantages of ROM resource, improve the
resource utilization rate, reduces the design cost of hardware. The
algorithm makes the numerically controlled oscillator and digital
frequency mixer two function together, eliminating the2 multipliers, using
CORDIC algorithm CORDIC rotating shift - phase flow structure, realizes
the design of digital down converter, its validity is verified by
simulation.                                                    
KEYWORDS  Numerically controlled oscillator     The CORDIC algorithm
Serial transmission      Display module   FPGA 本科生毕业设计说明书（论文）
目 录  
1  引言    2
1.1 背景及意义    2
1.2 数控振荡器 NCO  .  3
2 数控振荡器的原理 .  5
2.1 NCO 的基本原理   5
2.2 NCO 的性能指标   6 基于CORDIC算法的数控振荡器设计+文献综述:http://www.751com.cn/tongxin/lunwen_4069.html