Chapter 3 investigates the capacity improvement in cdma multi - cellular system with base - station smart antenna . we consider the effects of multipath interference , thermal noise , path loss , processing gain and voice activity factor . and introduces multiuser detection combined with smart antenna 考虑了多径干扰、热噪声、路径损耗、处理增益和语音激活因子的影响；并介绍了与智能天线技术相结合的多用户检测技术。
First in this paper , we review the development of radar signal processing and cfar detector , analyse the structure and principle of the signal processor , ca - cfar and os - cfar detectors . then , in view of the characteristic of prc cw signal , analyses the statistics characteristic of scattering bodies , models of target , noise , ground - clutter and weather - clutter are made . these lay a theoretic foundation of signal processing and cfar detector 然后,本文针对x波段伪随机m序列相位编码连续波信号体制,分析了各种散射体的统计特性,对雷达目标及检测背景噪声(热噪声、地杂波和气象杂波)进行了理论分析和统计检验,建立了目标及检测背景的目标模型,确立了信号处理和恒虚警检测的理论基础。
The master dissertation introduces passive correlative orientation system and base theory in signal dispose briefly in the first place . the system takes tv sound fm signal from tv satation signal . the power rate of tv station signal to sound signal is ten to one . in the case of submerged by mussy weave and machine ' s hot noise , dispersed target signal is feeble 系统采用电台的电视伴音调频信号，其中电台信号与伴音信号功率之比基本为10 ： 1 ，并且目标散射信号较弱，一般情况下淹没在杂波和机器热噪声之下，采用常规的脉冲检测方法很难对远距离的目标进行检测，而以电台直达信号作为参考与目标回波信号进行相关检测；系统中信号的相关处理会产生旁瓣，而强目标的旁瓣会影响附近的弱目标检测。
Most of the lectures on nbi suppression assume that the spread spectrum signal and the background noise are white . this assumption cannot stand up in digitalized receiver because of the if oversampling and digital low pass filtering in digitalized receiver . the code - aided optimal filtering is studied extensively in the circumstance of oversampling and colored background noise 以往的扩频抗干扰文献多将扩频信号和背景热噪声假设为白噪声,由于在数字正交解扩解调中采用过采样和数字低通滤波,这一假设在数字化扩频接收机中并不成立。
With the method of integral within ordered product of operators , we obtain the analytical expression of quantum information counterpart of mutual information . the coherent information , as a function of input thermal state power and thermal noise channel power , we discuss the upper and lower bound for quantum gaussian channel introduced by holevo - werner and by quantum codes 用正规乘积内的算符积分技术求出了互信息的量子对应物? ?相干信息用输入热噪声信号功率和信道热噪声功率表示的公式。讨论了由holevo和werner引入的量子高斯信道量子容量的上界及由量子编码所确定的下界。
The experimental results showed that the substrate of pyroelectric sensor could significantly affect the detectivity . the porous silicon dioxide and pet plastic film substrate could effectively decrease the thermal conduction and the thermal fluctuation noise of the pyroelectric element , increase the voltage responsivity and the detectivity obviously 结果表明，多孔氧化硅和pet塑料可有效降低热释电元件的对外热传导，明显提高传感器的电压响应率和降低热释电元件的热噪声。
Much study are made on the noise of ccd sensor , both the correlated - quadrupole - sampling and correlated - double - sampling techniques are used in this system . also , pilter cooler technique are used to keep the temperature of ccd chip about - 20 , reducing the thermal noise . usb2 . 0 interface technique is also used to communicate between the camera and host computer 其中着重对ccd传感器的去噪声技术进行了研究,采用了相关双采样和相关四采样的方法处理视频信号,并分别进行12bits和14bits的a / d转换;在系统中使用了半导体致冷片和反馈电路构建了致冷电路,使ccd的温度保持在- 20以减少热噪声;数据传输采用usb2 . 0接口规范以满足实时数据传输的要求。
A new if simulation signal digital model was developed , which has the ability to simulate the ocean return wave noise and the instrument thermal noise . by this simulation data , smle is successfully tested , and the rf ocean return wave simulator also worked correctly . it is difficult for altimeter to realize closed loop internal calibration with a large time - bandwidth product ( 4 )提出了雷达高度计海面回波中频仿真信号的数字模型，该模型具有仿真高度计海面回波噪声和仪器热噪声的功能；基于该模型的软件仿真器成功的对高度计跟踪器进行了验证；同时，该模型仿真的信号应用于雷达高度计射频回波模拟器也获得了成功。
Vco ’ s theory and parameters especially for the basic mechanism of phase noise are studied . the parasitic effects of rf - ic passive devices such as inductors and varactors and the design guidelines for the on - chip spiral inductors are included too . the accumulation - mode varactor , which has a higher quality factor value than the inversion - mode mos varactor , is studied in detail 研究电感和变容管这两种射频集成无源器件的寄生效应和射频mos晶体管的热噪声模型,提出集成电感的设计原则和优化方法,详细研究了一种新型的积累型mos可变电容,这种积累型mos变容管比一般的反型mos变容管有更高的品质因数。
That is the reason that all over the countries have never stopped researching for mask jamming technology of radar . at present , the mask jamming source mainly comes from the thermal noise and zener avalanche noise of semiconductor devices . but the noise ’ s quality isn ’ t stabile because of the differences of semiconductor devices each other and the changes of exterior conditions 目前采用的遮盖性干扰的噪声源主要来自半导体器件本身的热噪声或齐纳雪崩噪声,但各器件本身的不一致性和外界条件变化等因素使噪声输出质量不稳定;同时由于此类信号不能再生,不利于科学研究。
