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、产品分类介绍:  

A、射频微波元器件

->射频模块/功率管
->
频管
/高频/微波管
->
混频器
->
放大器
->
衰减器
->
双工器
->
功分器
->
隔离器
->开关/射频微波开关
->
低噪声管
->
温补晶振
/晶体振荡器
->
负载电阻
->
PIN二极管
->
PLL锁相环
->
通信IC
->
介质滤波器
->
声表滤波器
/SAW
->
混合耦合器
->
高频微波电容
->
高频微波电感

->特价库存微波元件

->电源系统专用元件

->高频功放模块

->特殊专用元件

->高频三极管

->无线电发射专用管发射管

->高频场效应管

->GaAs微波功率晶体管

->MOS双极性晶体管

->微波毫米波振荡器

->频率源/频率综合器

->倍频器/倍频器模块

->MMIC混频器

  同轴和波导混频器

->MMIC移相器及移相器模块

->MMIC功率放大器低噪放

->对数检波视频放大器

->MMIC KU到KA收发器

->MMIC开关及模块

->同轴及波导负载部件

->MMIC同轴及波导衰减器

->同轴定向耦合器部件

->适配器转换

->速调管、行波管检波器

->波导部件和旋转关节

->功分器合路器双工器

->毫米波测试设备

->限幅器

->高功率倍增器

->射频连接/接插/线缆

->射频微波材料

->军品高精度晶体振荡器

-> 通信专用元器件

-> 电子管/真空管/闸流管

-> FREESCALE/MOTOROLA

-> ERICSSON爱立信系列

-> NXP/PHILIPS飞利浦系列

-> TOSHIBA东芝系列

-> MITSUBISHI/RENESAS

-> M/A-COM系列

-> ASI系列

-> EUDYNA/FUJITSU富士通

-> HP/AGILENT/Avago

-> NEC日电系列

-> HITACHI/RENESAS日立

-> SONY索尼系列
->
UMS

-> Mini-circuits

-> SIRENZA

-> ALPHA

->  WJ

-> RFMD

-> APT

-> HITTITE

-> ST意法半导体

-> QUALCOMM高通

-> PDI

-> CML

 

B、光通讯元器件

->光电通讯元器件

->光耦/光电耦合器

->Agilent光模块

->AMP光模块

->SIEMENS光纤收发模块

->OCP光纤收发模块

->CISCO光纤收发模块

->GBIC光纤收发模块

->光纤收发

->常用光电元器件库存

 

C、二极管、三极管

->二极管/变容管/变阻管

->三极管/晶闸管/场效应管

->2SJ系列电子器件

D、无线收发、无线射频IC

E、无线收发模块

F、GSM/CDMA/GPRS通信模块

G、GPS模块/天线/方案

H、扩频模块/MODEM模块

I、遥控器/遥控开关/模块

J、通信继电器/干簧管

K、电源模块/模块电源

L、通信变压器

M、通信防雷器/TVS管

N、无线收发芯片和模组

O、数据通信芯片

 

二、产品图文介绍:

 
 
 
 
 
 
 

 

Doppler Effects(多普勒效应)

    Apparent change in the wave frequency (or in the period of periodic events) due to motion of wave source and/or observer is known as Doppler effect. In the 17th century (well before Doppler effect was predicted), Roemer (Danish astronomer) estimated the speed of light from the change in the revolution period of one of Jupiter's moons. When the earth is approaching Jupiter, the period is shortened, while receding, the period is elongated. The first animation shows wave patterns (surfaces of constant phase) emitted by a moving wave source. Wavelengths in front of the moving source are squeezed (shortened) according to and those behind are elongated,
where cw is the wave (sound) velocity and Vs is the velocity of the wave source. Therefore, the frequency of a wave source approaching (receding from) an observer is higher (lower) than the "true" frequency,Similar effect occurs when the observer is moving. For sound waves, the velocities of source and observer are well defined relative to air, the wave medium. For stationary sound source and moving observer, the sound speed appears to change (the wavelength remains the same). Therefore, the Doppler shifted frequency for a stationary sound source heard by a moving observer is given by where Vo is the velocity of the observer relative to air, + sign for the case of approaching and ?sign for the case of receding.

    For electromagnetic waves in vacuum, the velocity with respect to the wave medium (vacuum) is ill defined. In Doppler effect of electromagnetic waves, only the relative velocity between wave source and observer matters, where is the relative velocity between the wave source and observer normalized by the velocity of light c. The factor in the numerator, is due to intrinsic Doppler shift caused by time dilation effect.

    Some objects (e.g., supersonic planes) can move faster than sound waves. Animation below shows wave fronts emitted by a supersonic object when the Mach number is 2. No waves can exist outside the cone created by the object. When the cone surface hits an observer, sudden arrival of a sharp pulse is detected as shock wave. In vacuum, nothing can travel faster than light. However, in material media (glass, plastic, etc.), electromagnetic waves propagate in general at a speed slower than c. Therefore, if a relativistic charged particle with a velocity close to c enters, say, a plastic block, electromagnetic shock wave is emitted. This phenomenon is called Cerenkov radiation and is in wide use for detecting energetic particles.

    Doppler effect. Volocity of wave source = one half of the wave velocity. Wavelengths in front of the source are squeezed while those behind are elongated.

animate({[u*sin(t),u*cos(t),t=-Pi..Pi], [(u-1)*sin(t)*Heaviside(u-1)+.5,(u-1)*cos(t)*Heaviside(u-1),t=-Pi..Pi],
[(u-2)*sin(t)*Heaviside(u-2)+1.,(u-2)*cos(t)*Heaviside(u-2),t=-Pi..Pi],
[(u-3)*sin(t)*Heaviside(u-3)+1.5,(u-3)*cos(t)*Heaviside(u-3),t=-Pi..Pi],
[(u-4)*sin(t)*Heaviside(u-4)+2.,(u-4)*cos(t)*Heaviside(u-4),t=-Pi..Pi],
[(u-5)*sin(t)*Heaviside(u-5)+2.5,(u-5)*cos(t)*Heaviside(u-5),t=-Pi..Pi],
[(u-6)*sin(t)*Heaviside(u-6)+3.,(u-6)*cos(t)*Heaviside(u-6),t=-Pi..Pi],
[(u-7)*sin(t)*Heaviside(u-7)+3.5,(u-7)*cos(t)*Heaviside(u-7),t=-Pi..Pi]},
u=0..8,view=[-8..8,-8..8],frames=40,color=red);

Velocity of wave source = twice of the wave velocity. Formation of shock wave. animate({[u*sin(t),u*cos(t),t=-Pi..Pi], [(u-1)*sin(t)*Heaviside(u-1)+2,(u-1)*cos(t)*Heaviside(u-1),t=-Pi..Pi],
[(u-2)*sin(t)*Heaviside(u-2)+4,(u-2)*cos(t)*Heaviside(u-2),t=-Pi..Pi],
[(u-3)*sin(t)*Heaviside(u-3)+6,(u-3)*cos(t)*Heaviside(u-3),t=-Pi..Pi],
[(u-4)*sin(t)*Heaviside(u-4)+8,(u-4)*cos(t)*Heaviside(u-4),t=-Pi..Pi],
[(u-5)*sin(t)*Heaviside(u-5)+10,(u-5)*cos(t)*Heaviside(u-5),t=-Pi..Pi],
[(u-6)*sin(t)*Heaviside(u-6)+12,(u-6)*cos(t)*Heaviside(u-6),t=-Pi..Pi],
[(u-7)*sin(t)*Heaviside(u-7)+14,(u-7)*cos(t)*Heaviside(u-7),t=-Pi..Pi]},
u=0..8,view=[-8..16,-8..8],frames=40,color=red);

> interface(plotdevice=inline):
with(plots):
implicitplot({x^2+y^2=4.5^2,(x-2)^2+y^2=3.5^2,(x-4)^2+y^2=2.5^2,
(x-6)^2+y^2=1.5^2,(x-8)^2+y^2=0.5^2,x+1.732*y=9,x-1.732*y=9},x=-5..9,y=-5..5,numpoints=1000);

 

 

 

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商运达射频微波光电产品网:HTTP://www.rfoe.net/  商运达传感器专家仪器仪表世界网:http://www.sensor-ic.com/

商运达智能工控公共安全网:http://www.pc-ps.net/         商运达电子元器件网:http://www.sunstare.com/

商运达军工产品网:hrrp://www.Junpinic.com/      商运达单片机专用电路网://www.icasic.com/

商运达实业科技产品网://www.sunstars.cn/   射频微波光电元器件销售热线:

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    电话:0755-83396822 83397033   

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    北京分公司:北京海淀区知春路132号中发电子大厦3097  TEL4006579498  18927445855  13823791822  FAX010-62543996 

    上海分公司:上海市北京东路668号上海賽格电子市场D125  TEL4006571586  56703037  13823676822  FAX021-56703037

    西安分公司:西安高新开发区20(中国电子科技集团导航技术研究所西安劳动南路88号电子商城二楼D23 

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