Wireless communications has become a field of enormous scientific and economic interest. Recent success stories include 2G and 3G cellular voice and data services (e.g., GSM and UMTS), wireless local area networks (WiFi/IEEE 802.11x), wireless broadband access (WiMAX/IEEE 802.16x), and digital broadcast systems (DVB, DAB, DRM). On the physical layer side, traditional designs typically assume that the radio channel remains constant for the duration of a data block. However, researchers and system designers are increasingly shifting their attention to CHANNELs that may vary within a block. In addition to time dispersion caused by multipath propagation, these rapidly time-varying CHANNELs feature frequency dispersion resulting from the Doppler effect. They are, thus, often referred to as being “doubly dispersive.”
标签: Time-Varying CHANNELs
上传时间: 2020-06-01
上传用户:shancjb
The explosion in demand for wireless services experienced over the past 20 years has put significant pressure on system designers to increase the capacity of the systems being deployed. While the spectral resource is very scarce and practically exhausted, the biggest possibilities are predicted to be in the areas of spectral reuse by unlicensed users or in exploiting the spatial dimension of the wireless CHANNELs. The former approach is now under intense development and is known as the cogni- tive radio approach (Haykin 2005).
标签: Multi-Antenna Wireless CHANNELs Modeling
上传时间: 2020-06-01
上传用户:shancjb
The A706 series is a high voltage Boost driver with 6 CHANNELs adjustable constant current regula
上传时间: 2013-06-09
上传用户:青春给了作业95
Digital-to-analog converters (DACs) are prevalent inindustrial control and automated test applications.General-purpose automated test equipment often requiresmany CHANNELs of precisely controlled voltagesthat span several voltage ranges. The LTC2704 is ahighly integrated 16-bit, 4-channel DAC for high-endapplications. It has a wide range of features designed toincrease performance and simplify design.
上传时间: 2013-11-22
上传用户:元宵汉堡包
The 14-bit LTC2351-14 is a 1.5Msps, low power SARADC with six simultaneously sampled differential inputCHANNELs. It operates from a single 3V supply and featuressix independent sample-and-hold amplifi ers and a singleADC. The single ADC with multiple S/HAs enables excellentrange match (1mV) between CHANNELs and channel-toCHANNELskew (200ps).
上传时间: 2014-12-23
上传用户:天诚24
介绍了一种基于C8051F020单片机的多路压力测量仪。该测量仪选用电阻应变式压力传感器采集压力信号,并经放大电路处理后送入C8051F020单片机,再由C8051F020单片机内部的A/D转换器将采集到的压力信号进行模数转化,然后分别对数据进行存储和显示。该测量仪能测量6路压力信号,并且各测量点都能单独检测和设置。由于采用了C8051F020单片机,简化了硬件电路,增强了抗干扰能力,使得测量仪具有测量精度高,冲击小等特点。 Abstract: A measurement apparatus for multi-channel pressure based on single chip microcomputer is introduced.It can measure 6 CHANNELs signal of the pressure,and the pressure measure points can be detection and located individually.The pressure signal sampling is obtained by resistor stress-type pressure sensors,the digital signals of 6 CHANNELs are collected through amplifying and adjustment circuit of pressure signals and internal integrated A/D converter of MCU.Finally,and it realizes the function to store and display data separately.C8051F020 was used to made hardware circuit simple,and it also enhanced the anti-interference ability.It features high precision and little impact.
上传时间: 2013-11-16
上传用户:yare
主要介绍构成记忆示波器的STC12C5408AD增强型单片机8通道10位模数转换功能的设置、应用和具体的汇编程序设计,以及PC机串行通讯和图形显示的高速汇编程序的设计要点,并列举实例说明其应用效果。 Abstract: The configuration, applications and the designs for? compiling program of the memorial oscillograph of 10 bits A/D conversation are introduced. It’s bases on STC12C5408AD 8? CHANNELs? single-chip? computer? in? enhancement? mode. It also recommends the devising essentials of high speed compiling program for PC serial communication and graphics display, lists examples to explain its effects in using.
上传时间: 2013-10-10
上传用户:adada
The PCA9540B is a 1-of-2 bidirectional translating multiplexer, controlled via the I2C-bus.The SCL/SDA upstream pair fans out to two SCx/SDx downstream pairs, or CHANNELs.Only one SCx/SDx channel is selected at a time, determined by the contents of theprogrammable control register.
上传时间: 2014-12-28
上传用户:nshark
The PCA9544A provides 4 interrupt inputs, one for each channeland one open drain interrupt output. When an interrupt is generated byany device, it will be detected by the PCA9544A and the interruptoutput will be driven LOW. The channel need not be active fordetection of the interrupt. A bit is also set in the control byte.Bits 4 – 7 of the control byte correspond to CHANNELs 0 – 3 of thePCA9544A, respectively. Therefore, if an interrupt is generated byany device connected to channel 2, the state of the interrupt inputs isloaded into the control register when a read is accomplished.Likewise, an interrupt on any device connected to channel 0 wouldcause bit 4 of the control register to be set on the read. The mastercan then address the PCA9544A and read the contents of thecontrol byte to determine which channel contains the devicegenerating the interrupt. The master can then reconfigure thePCA9544A to select this channel, and locate the device generatingthe interrupt and clear it. The interrupt clears when the deviceoriginating the interrupt clears.
标签: 4channel multiple 9544A 9544
上传时间: 2014-12-28
上传用户:潜水的三贡
The PCA9542A is a 1-of-2 bidirectional translating multiplexer, controlled via the I2C-bus.The SCL/SDA upstream pair fans out to two SCx/SDx downstream pairs, or CHANNELs.Only one SCx/SDx channel is selected at a time, determined by the contents of theprogrammable control register. Two interrupt inputs, INT0 and INT1, one for each of theSCx/SDx downstream pairs, are provided. One interrupt output, INT, which acts as anAND of the two interrupt inputs, is provided.
上传时间: 2013-12-07
上传用户:europa_lin