排序方式: 共有55条查询结果,搜索用时 15 毫秒
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A 3.1-4.8 GHz CMOS receiver for MB-OFDM UWB 总被引:1,自引:1,他引:0
An integrated fully differential ultra-wideband CMOS receiver for 3.1-4.8 GHz MB-OFDM systems is presented. A gain controllable low noise amplifier and a merged quadrature mixer are integrated as the RF front-end. Five order Gm-C type low pass filters and VGAs are also integrated for both I and Q IF paths in the receiver. The ESD protected chip is fabricated in a Jazz 0.18μm RF CMOS process and achieves a maximum total voltage gain of 65 dB, an AGC range of 45 dB with about 6 dB/step, an averaged total noise figure of 6.4 to 8.8 dB over 3 bands and an in-band IIP3 of-5.1 dBm. The receiver occupies 2.3 mm2 and consumes 110 mA from a 1.8 V supply including test buffers and a digital module. 相似文献
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《半导体学报》2009,30(12)
A fully integrated low power RF transmitter for a WiMedia 3.1-4.8 GHz multiband orthogonal frequency division multiplexing ultra-wideband system is presented. With a separate transconductance stage, the quadrature up-conversion modulator achieves high linearity with low supply voltage. The co-design of different resonant frequencies of the modulator and the differential to single (D2S) converter ensures in-band gain flatness. By means of a series inductor peaking technique, the D2S converter obtains 9 dB more gain without extra power consumption. A divided-by-2 divider is used for carrier signal generation. The measurement results show an output power between -10.7 and -3.1 dBm with 7.6 dB control range, an OIP3 up to 12 dBm, a sideband rejection of 35 dBc and a carrier rejection of 30 dBc. The ESD protected chip is fabricated in the Jazz 0.18/zm RF CMOS process with an area of 1.74 mm~2 and only consumes 32 mA current (at 1.8 V) including the test associated parts. 相似文献
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讨论了基于MB—OFDM方案的超宽带通信系统,在此方案中,整个可用频带被分为多个528MHz的子带,每个子带上采用OFDM技术传输信息,数据通过时频码在不同的子带上传输。主要介绍了频带划分,系统参数,实现结构等问题,同DS—CDMA方案进行了比较。最后展望了UWB无线通信的发展前景。 相似文献
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提出了一种新的超宽带通信实现方式,该方式基于MB-OFDM技术,用户数据在时域和频域交织传输,形成了新的MB-TFI(时频交织)-OFDM方式.结合MBOA实际案例,分析了MB-OFDM芯片的商业化和产品化进程及前景展望.研究表明,MB-TFI-OFDM UWB技术以它独特的优势,将会促进MB-OFDM方案的发展,得到越来越多厂商的支持与应用,从而有希望成为WPAN物理层的标准技术. 相似文献
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多速率超宽带通信系统中天线传输性能的研究 总被引:1,自引:0,他引:1
利用实验测量结合数值仿真的方法,研究了特定室内环境中,不同形状超宽带单极子天线对不同速率多带正交频分(MB-OFDM)超宽带通信系统传输性能的影响.仿真与实验中,MB-OFDM平台采用MATLAB的simulink工具实现,天线与传播环境构成的广义信道特性则通过矢量网络分析仪进行测量.结果表明,单极子天线形状对不同速率MB-OFDM系统的传输误比特率性能有显著影响,文章的方法可用于多速率超宽带通信系统收发天线的优选和性能评价. 相似文献
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本论文实现了频率为7.656GHz全集成正交输出CMOS锁相环。该锁相环可以用作MB-OFDM超宽带频率综合器的一个基本模块。为了使环路快速稳定,该锁相环采用整数型结构,指定输入参考频率为66MHz,并且采用了一个宽带的正交压控振荡器,把两个交叉耦合LC压控振荡器通过底部串联耦合来产生正交载波。在0.18微米CMOS工艺和1.5V电源电压下,该锁相环消耗电流16mA(包含驱动电路),测得相位噪声在1MHz频偏处为-109 dBc/Hz。其中测得正交压控振荡器的频率调谐范围为6.95GHz至8.73GHz。整个芯片的核心面积为1×0.5mm2。 相似文献
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正A monolithic RF transceiver for an MB-OFDM UWB system in 3.1-4.8 GHz is presented.The transceiver adopts direct-conversion architecture and integrates all building blocks including a gain controllable wideband LNA,a I/Q merged quadrature mixer,a fifth-order Gm-C bi-quad Chebyshev LPF/VGA,a fast-settling frequency synthesizer with a poly-phase filter,a linear broadband up-conversion quadrature modulator,an active D2S converter and a variablegain power amplifier.The ESD protected transceiver is fabricated in Jazz Semiconductor's 0.18-μm RF CMOS with an area of 6.1 mm~2 and draws a total current of 221 mAfrom 1.8-V supply.The receiver achieves a maximum voltage gain of 68 dB with a control range of 42 dB in 6 dB/step,noise figures of 5.5-8.8 dB for three sub-bands,and an inband /out-band IIP_3 better than-4 dBm/+9 dBm.The transmitter achieves an output power ranging from-10.7 to-3 dBm with gain control,an output P_(1dB) better than-7.7 dBm,a sideband rejection about 32.4 dBc,and LO suppression of 31.1 dBc.The hopping time among sub-bands is less than 2.05 ns. 相似文献
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无线个域网是当前无线通信研究的热点之一,IEEE802.15.3a对发射信号的功率、短距离的高速率信息传输等方面提出了更高的要求。由于FCC对超宽带信号进行了重新定义,使得产生超宽带信号的方式并不局限在冲激无线电范畴,利用OFDM技术与DS CDMA技术也能实现超宽带通信。当前IEEE802.15.3a的2种主流技术(MB OFDM和DSCDMA)之间争执不下,将对2种技术进行详细的比较,比较结果显示,在当前的技术水平下,MB OFDM技术具有一定的优势。 相似文献
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