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Photonics-based radar with balanced I/Q de-chirping for interference-suppressed high-resolution detection and imaging 被引量:11
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作者 XINGWEI YE FANGZHENG ZHANG +1 位作者 YUE YANG SHILONG PAN 《Photonics Research》 SCIE EI CSCD 2019年第3期265-272,共8页
Photonics-based radar with a photonic de-chirp receiver has the advantages of broadband operation and real-time signal processing, but it suffers from interference from image frequencies and other undesired frequency-... Photonics-based radar with a photonic de-chirp receiver has the advantages of broadband operation and real-time signal processing, but it suffers from interference from image frequencies and other undesired frequency-mixing components, due to single-channel real-valued photonic frequency mixing. In this paper, we propose a photonicsbased radar with a photonic frequency-doubling transmitter and a balanced in-phase and quadrature(I/Q)de-chirp receiver. This radar transmits broadband linearly frequency-modulated signals generated by photonic frequency doubling and performs I/Q de-chirping of the radar echoes based on a balanced photonic I/Q frequency mixer, which is realized by applying a 90° optical hybrid followed by balanced photodetectors. The proposed radar has a high range resolution because of the large operation bandwidth and achieves interference-free detection by suppressing the image frequencies and other undesired frequency-mixing components. In the experiment, a photonics-based K-band radar with a bandwidth of 8 GHz is demonstrated. The balanced I/Q de-chirping receiver achieves an image-rejection ratio of over 30 dB and successfully eliminates the interference due to the baseband envelope and the frequency mixing between radar echoes of different targets. In addition, the desired dechirped signal power is also enhanced with balanced detection. Based on the established photonics-based radar,inverse synthetic aperture radar imaging is also implemented, through which the advantages of the proposed radar are verified. 展开更多
关键词 Photonics-based RADAR i/q de-chirping interference-suppressed HiGH-RESOLUTiON detection
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200 MHz带宽基带信号发生器的设计与实现 被引量:5
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作者 薛晓男 李增红 《国外电子测量技术》 2017年第10期69-72,共4页
介绍了基于FPGA的基带信号发生器设计方案,主要叙述了成型滤波以及任意重采样内插比等关键技术。该基带信号发生器不仅实现了标准数字调制格式的基带信号发生,而且通过FPGA内部的并行架构设计,实现了500 MHz的高速数据速率,I/Q带宽达到2... 介绍了基于FPGA的基带信号发生器设计方案,主要叙述了成型滤波以及任意重采样内插比等关键技术。该基带信号发生器不仅实现了标准数字调制格式的基带信号发生,而且通过FPGA内部的并行架构设计,实现了500 MHz的高速数据速率,I/Q带宽达到200 MHz。将其应用于矢量信号发生器中,既实现了PSK、ASK、FSK、MSK、QAM等标准数字调制格式的矢量信号,又实现了400 MHz矢量调制带宽。经过测试,在4 M码元速率的情况下,QPSK和512QAM调制格式的EVM分别达到0.7%和1.0%;400 MHz带宽的矢量调制信号频响小于1dB。 展开更多
关键词 基带信号 成型滤波 任意重采样内插比 i q EVM 矢量调制带宽
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零中频处理缺陷分析及改进初探 被引量:5
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作者 庞敏 林霞 刘江洪 《电子信息对抗技术》 2008年第3期18-21,70,共5页
在电子战系统中为了拓展信号处理带宽越来越多地采用I/Q变频体制,但是,在IQ变频体制中,当变频后的中频信号频率接近零时,信号检测和处理存在一些困难,有可能使系统性能下降。文章分析了IQ变频体制中零中频点对信号截获和干扰的影响,提... 在电子战系统中为了拓展信号处理带宽越来越多地采用I/Q变频体制,但是,在IQ变频体制中,当变频后的中频信号频率接近零时,信号检测和处理存在一些困难,有可能使系统性能下降。文章分析了IQ变频体制中零中频点对信号截获和干扰的影响,提出了改进措施,并对其可行性进行了分析,在改进零中频处理缺陷方面进行了有益的探索。 展开更多
关键词 i/q 零中频处理
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ADAPTIVE CALIBRATION OF I AND Q MISMATCH IN QUADRATURE RECEIVER 被引量:3
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作者 YangXuexian ZhangQunying 《Journal of Electronics(China)》 2002年第2期187-191,共5页
The mismatch of ill-phase and quadrature channels in quadrature receiver affects and constrains radar detection performance in coherent radar. It is necessary to keep the in-phase and quadrature branches symmetrical. ... The mismatch of ill-phase and quadrature channels in quadrature receiver affects and constrains radar detection performance in coherent radar. It is necessary to keep the in-phase and quadrature branches symmetrical. In this letter, an adaptive method t.o detect imbalance parameters is derived by means of evaluating channel errors from the received signal .sequences. No matter how the bias degree of the gain and phase errors in I/Q channels are. the proposed adaptive scheme can obtain good calibration results. And the inquired calculations are only a few multiplications and additions. No need of a special test signal, the introduced method is simple to implement and easy to operate. 展开更多
关键词 quadrature receiver i/q mismatch Adaptive' calibration
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An I/Q mixer with an integrated differential quadrature all-pass filter for on-chip quadrature LO signal generation 被引量:2
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作者 Najam Muhammad Amin 王志功 李智群 《Journal of Semiconductors》 EI CAS CSCD 2015年第5期81-89,共9页
A down-conversion in-phase/quadrature (l/Q) mixer employing a folded-type topology, integrated with a passive differential quadrature all-pass filter (D-QAF), in order to realize the final down-conversion stage of... A down-conversion in-phase/quadrature (l/Q) mixer employing a folded-type topology, integrated with a passive differential quadrature all-pass filter (D-QAF), in order to realize the final down-conversion stage of a 60 GHz receiver architecture is presented in this work. Instead of employing conventional quadrature generation techniques such as a polyphase filter or a frequency divider tbr the local oscillator (LO) of the mixer, a passive D-QAF structure is employed. Fabricated in a 65 nm CMOS process, the mixer exhibits a voltage gain of 7-8 dB in an intermediate frequency (IF) band ranging from 10 MHz-1.75 GHz. A fixed LO frequency of 12 GHz is used to down-convert a radio frequency (RF) band of 10.25-13.75 GHz. The mixer displays a third order input referred intercept point (IIP3) ranging from -8.75 to -7.37 dBm for a fixed IF frequency of 10 MHz and a minimum single-sideband noise figure (SSB-NF) of 11.3 dB. The mixer draws a current of 6 mA from a 1.2 V supply voltage dissipating a power of 7.2 mW. 展开更多
关键词 folded i/q mixer LO generation differential quadrature all-pass filter
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采用I/Q矢量调制器的单通道单脉冲信道合成方案研究 被引量:2
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作者 张根祥 《现代电子技术》 2012年第12期123-125,129,共4页
三通道单脉冲跟踪体制存在的问题是和/差信号在各自通道传输时的幅相不一致校准困难,设备复杂,成本较高。采用频分和时分复用技术将三通道(或双通道)合成为单通道的单脉冲天线跟踪系统在遥测、遥感、通信等领域已得到广泛的应用。这里... 三通道单脉冲跟踪体制存在的问题是和/差信号在各自通道传输时的幅相不一致校准困难,设备复杂,成本较高。采用频分和时分复用技术将三通道(或双通道)合成为单通道的单脉冲天线跟踪系统在遥测、遥感、通信等领域已得到广泛的应用。这里给出一种采用I/Q矢量调制器将双通道组合成单通道的单脉冲信道合成方案,同时给出调幅包络检测后角误差电压分解方法。 展开更多
关键词 单通道单脉冲 i/q 矢量调制器 合成方案
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中频窄带数字正交接收机的设计与实现 被引量:2
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作者 杨洪丰 王磊 《中国电子科学研究院学报》 2007年第1期102-107,共6页
设计了中频窄带数字正交接收机,该正交接收机是基于PCI结构,带有一路AD及一片AD6620数字下变频处理芯片,用PC机可以方便实时地进行控制。实验结果表明该接收机结构简单、易于实现,而且精度高、误差小。
关键词 信号处理 数字下变频器 i/q
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A 2-mW 50-dB DR wideband hybrid AGC for a GNSS receiver in 65 nm CMOS 被引量:1
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作者 续阳 池保勇 +2 位作者 徐阳 祁楠 王志华 《Journal of Semiconductors》 EI CAS CSCD 2012年第7期94-101,共8页
A low-power wideband hybrid automatic gain control (AGC) loop for a GNSS receiver is presented. Single AGC in the I/Q path is composed of four-stage programmable gain amplifiers (PGAs), a differential peak detecto... A low-power wideband hybrid automatic gain control (AGC) loop for a GNSS receiver is presented. Single AGC in the I/Q path is composed of four-stage programmable gain amplifiers (PGAs), a differential peak detector, two comparators, a control algorithm logic, a decoder and the reference voltage source. Besides being controlled by an AGC loop, the gain of PGAs could altematively be controlled by an off-chip digital baseband processor through the SPI interface. To obtain low power consumption and noise, an improved source degenerated amplifier is adopted, and the I/Q path phase mismatch within the ±5° range is calibrated with 0.2° accuracy. Implemented in 65 nm CMOS, the measured PGA total gains range from 9.8 to 59.5 dB with an average step of 0.95 dB and simulated bandwidth of more than 110 MHz. The settling time is about 180 μs with 80% AM input with measured signal power from -76.7 to -56.6 dBm from a radio-frequency amplifier (RFA) input port, and also reduces to 90 #s with clock frequency doubling. The single AGC consumes almost 0.8 mA current from the 2.5-V supply and occupies an area of 750 × 300 μm2. 展开更多
关键词 AGC HYBRiD GNSS PGAs i/q phase calibration settling time
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I/Q mismatch calibration based on digital baseband 被引量:1
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作者 雷倩倩 赵二虎 +3 位作者 袁芳 林敏 李连碧 冯松 《Journal of Semiconductors》 EI CAS CSCD 2013年第7期160-166,共7页
A novel I/Q mismatch calibration technique based on a digital baseband for a direct conversion transmitter is implemented in TSMC 0.13μm CMOS technology.The proposed technique finishes a calibration task, which only ... A novel I/Q mismatch calibration technique based on a digital baseband for a direct conversion transmitter is implemented in TSMC 0.13μm CMOS technology.The proposed technique finishes a calibration task, which only needs a calibration chain to detect mismatches and then transmit them to the digital baseband.Simulation results show that the calibrated errors of the proposed technique are less than 7%.The measurement results indicate the function of the proposed technique is correct,but the performance should be improved further. 展开更多
关键词 i/q mismatch direct conversion transmitter CALiBRATiON
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Optimization of Mapping Rule of Bit-Interleaved Turbo Coded Modulation with 16QAM 被引量:1
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作者 费泽松 杨宇 +1 位作者 刘林南 匡镜明 《Journal of Beijing Institute of Technology》 EI CAS 2005年第1期18-21,共4页
Optimization of mapping rule of bit-interleaved Turbo coded modulation with 16 quadrature amplitude modulation (QAM) is investigated based on different impacts of various encoded bits sequence on Turbo decoding perfor... Optimization of mapping rule of bit-interleaved Turbo coded modulation with 16 quadrature amplitude modulation (QAM) is investigated based on different impacts of various encoded bits sequence on Turbo decoding performance. Furthermore, bit-interleaved in-phase and quadrature phase (I-Q) Turbo coded modulation scheme are designed similarly with I-Q trellis coded modulation (TCM). Through performance evaluation and analysis, it can be seen that the novel mapping rule outperforms traditional one and the I-Q Turbo coded modulation can not achieve good performance as expected. Therefore, there is not obvious advantage in using I-Q method in bit-interleaved Turbo coded modulation. 展开更多
关键词 binary Turbo coded modulation quadrature amplitude modulation (qAM) mapping rule in-phase and quadrature (i-q) coded modulation
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数字I/Q射频鉴相器的研制
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作者 俞路阳 殷重先 刘德康 《核电子学与探测技术》 CAS CSCD 北大核心 2006年第2期168-172,共5页
详细介绍了一种用于直线加速器的数字化I/Q射频鉴相器。该鉴相器使用双平衡混频器作为相位探测器,由于采用了商业化的PXI模块,控制和数据获取系统都是基于PXI总线;软件采用曲线拟合算法。实验室的测试表明该系统具有分辨率高,重复性好... 详细介绍了一种用于直线加速器的数字化I/Q射频鉴相器。该鉴相器使用双平衡混频器作为相位探测器,由于采用了商业化的PXI模块,控制和数据获取系统都是基于PXI总线;软件采用曲线拟合算法。实验室的测试表明该系统具有分辨率高,重复性好,可靠性强等特点。 展开更多
关键词 PXi i/q DBM RF
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RF power and I/Q imbalance calibration in B3G/4G MIMO-OFDM systems
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作者 LI Ya-zhuo ZHOU Ming-yu ZHANG Ping 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2007年第2期89-93,124,共6页
Radio frequency (RF) front-end nonidealities in multi-input and multi-output (MIMO) systems are more serious than in single-input and single-output systems and must be calibrated. According to the effects of RF po... Radio frequency (RF) front-end nonidealities in multi-input and multi-output (MIMO) systems are more serious than in single-input and single-output systems and must be calibrated. According to the effects of RF power and in-phase/quadrature-phase (I/Q) imbalance, calibration methods for multi-input and multi-output-orthogonal frequency division multiplexing (MIMC-OFDM) systems in transmitter and interference in receiver are improved, respectively, in this article Furthermore, a calibration scheme including I/Q imbalance errors and amplitude variations is proposed and implemented in the B3G/4G time division duplex communication system. Simulation results show that the calibration algorithms are feasible, and the bit error rate (BER) performances for MIMO-OFDM systems are improved after calibrations. 展开更多
关键词 calibration B3G/4G MiMO-OFDM front-end i/q imbalance
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I-Q DRFM的系统建模仿真
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作者 冯锁 《巢湖学院学报》 2007年第3期74-78,共5页
本文给出了DRFM系统的仿真模型,并详细分析I-Q信道不平衡性及采样频率对输出信号频谱的影响,计算机仿真结果证明了模型与理论分析的正确性.该模型可为DRFM设计提供参考,具有实用价值。
关键词 i-q DRFM SiMULiNK 信道不平衡性 谐波 交调信号
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A 434/868 MHz CMOS low-IF receiver with I/Q imbalance calibration for SRDs application
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作者 李娟 赵冯 +1 位作者 叶国敬 洪志良 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2009年第3期97-103,共7页
A receiver for SRDs implemented by the 0.35μm CMOS process is presented. The receiver, together with the ADC, power amplifier (PA), frequency synthesizer and digital baseband has been integrated into a single chip ... A receiver for SRDs implemented by the 0.35μm CMOS process is presented. The receiver, together with the ADC, power amplifier (PA), frequency synthesizer and digital baseband has been integrated into a single chip solution. Low cost and low power requirements are met by optimizing the receiver architecture and circuit topology. A simple mixed-signal mode I/Q imbalance calibration circuit is proposed to enhance the IRR (image rejection ratio) so as to raise the BER. From a single 3 V power supply, the receiver consumes 5.9 mA. The measurement result shows that the receiver achieves reference sensitivity of-60 dBm and a control gain of 60 dB. The S11 reaches -20 dB at 433 MHz and -10 dB at 868 MHz without off-chip impedance match network. The die area is only 2 mm^2 including the bias circuit. 展开更多
关键词 short range device LOW-POWER LOW-COST RECEiVER i/q imbalance calibration
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A Novel Approach to Blind I/Q Mismatch &Carrier Offset Compensation
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作者 Sunita Panda Sasmita Kumari Padhy Siba P. Panigrahi 《Journal of Signal and Information Processing》 2011年第1期18-25,共8页
This paper proposes a novel approach for I/Q mismatch compensation. Simulation results proves the superior per-formance of the proposed technique.
关键词 Channel EqUALiZATiON i/q MiSMATCH compensation
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基于单位取样响应移位的采样时间差消除方法
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作者 王国庆 卢焕章 黎湘 《信号处理》 CSCD 北大核心 2010年第6期923-929,共7页
本文提出了一种工程上实用的采样时间差消除方法——单位取样响应移位法。该方法将采样时间差的消除过程与后续的数字信号处理结合起来,相当于零计算量完成了采样时间差的消除过程。结合LFM信号的匹配滤波过程,验证了该方法的性能。给... 本文提出了一种工程上实用的采样时间差消除方法——单位取样响应移位法。该方法将采样时间差的消除过程与后续的数字信号处理结合起来,相当于零计算量完成了采样时间差的消除过程。结合LFM信号的匹配滤波过程,验证了该方法的性能。给出了基于该方法的正交解调结构设计,新的结构优化了基于LFM信号的数字正交解调处理流程,节省了硬件资源与处理时间,易于工程实现。在性能允许的前提下,适合于大时宽带宽LFM信号的直接中频采样数字正交解调。 展开更多
关键词 i/q 采样时间差 单位取样响应移位法 匹配滤波
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An anti-image interference quadrature IF architecture for satellite receivers
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作者 He Weidong Lu Xiaochun +1 位作者 He Chengyan James Torley 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2014年第4期955-963,共9页
Since Global Navigation Satellite System(GNSS) signals span a wide range of frequency, wireless signals coming from other communication systems may be aliased and appear as image interference. In quadrature intermed... Since Global Navigation Satellite System(GNSS) signals span a wide range of frequency, wireless signals coming from other communication systems may be aliased and appear as image interference. In quadrature intermediate frequency(IF) receivers, image aliasing due to in-phase and quadrature(I/Q) channel mismatches is always a big problem. I/Q mismatches occur because of gain and phase imbalances between quadrature mixers and capacitor mismatches in analog-to-digital converters(ADC). As a result, the dynamic range and performance of a receiver are severely degraded. In this paper, several popular receiver architectures are summarized and the image aliasing problem is investigated in detail. Based on this analysis, a low-IF architecture is proposed for a single-chip solution and a novel and feasible anti-image algorithm is investigated. With this anti-image digital processing, the image reject ratio(IRR) can reach approximately above50 dB, which relaxes image rejection specific in front-end circuit designs and allows cheap and highly flexible analog front-end solutions. Simulation and experimental data show that the antiimage algorithm can work effectively, robustly, and steadily. 展开更多
关键词 Complex LMS image reject iNTERFERENCES i/q mismatches Receiver architecture
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A 220–1100 MHz low phase-noise frequency synthesizer with wide-band VCO and selectable I/Q divider
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作者 陈华 龚任杰 +4 位作者 程序 张玉琳 高众 郭桂良 阎跃鹏 《Journal of Semiconductors》 EI CAS CSCD 2014年第12期83-93,共11页
This paper presents a low phase-noise fractional-N frequency synthesizer which provides an inphase/quadrature-phase(I/Q) signal over a frequency range of 220–1100 MHz for wireless networks of industrial automation... This paper presents a low phase-noise fractional-N frequency synthesizer which provides an inphase/quadrature-phase(I/Q) signal over a frequency range of 220–1100 MHz for wireless networks of industrial automation(WIA) applications. Two techniques are proposed to achieve the wide range. First, a 1.4–2.2 GHz ultralow gain voltage-controlled oscillator(VCO) is adopted by using 128 tuning curves. Second, a selectable I/Q divider is employed to divide the VCO frequency by 2 or 3 or 4 or 6. Besides, a phase-switching prescaler is proposed to lower PLL phase noise, a self-calibrated charge pump is used to suppress spur, and a detect-boosting phase frequency detector is adopted to shorten settling time. With a 200 k Hz loop bandwidth, lowest measured phase noise is 106 dBc/Hz at a 10 k Hz offset and 131 dBc/Hz at a 1 MHz offset. Fabricated in the TSMC 0.18 μm CMOS process, the synthesizer occupies a chip area of 1.2 mm^2, consumes only 15 m W from the 1.8 V power supply,and settles within 13.2 s. The synthesizer is optimized for the WIA applications, but can also be used for other short-range wireless communications, such as 433, 868, 916 MHz ISM band applications. 展开更多
关键词 LC voltage-controlled oscillator(VCO) i/q divider phase-switching prescaler charge pump phase-locked loop(PLL) low phase noise wide band frequency synthesizer
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零中频技术在电子系统中的应用
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作者 李雪峥 冯来 《遥测遥控》 2011年第3期64-67,共4页
零中频技术已经成为通信发展的全新方向,能够大幅度提高通信芯片的集成度和数字处理能力。在电子系统中,为了拓展信号处理带宽,越来越多地采用I/Q变频体制,其突出优点是不需要中频放大、滤波、变频等电路,从而极大地减小了系统的体积、... 零中频技术已经成为通信发展的全新方向,能够大幅度提高通信芯片的集成度和数字处理能力。在电子系统中,为了拓展信号处理带宽,越来越多地采用I/Q变频体制,其突出优点是不需要中频放大、滤波、变频等电路,从而极大地减小了系统的体积、重量、功耗和成本。介绍零中频的特点,对正交上变频进行分析,给出零中频技术在电子系统中的应用实例。 展开更多
关键词 i/q 零中频 正交上变频 电子系统
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I-Q DRFM的系统建模仿真
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作者 冯锁 《北京教育学院学报(自然科学版)》 2007年第5期11-15,27,共6页
本文给出了DRFM系统的仿真模型,并详细分析I-Q信道不平衡性及采样频率对输出信号频谱的影响,计算机仿真结果证明了模型与理论分析的正确性。该模型可为DRFM设计提供参考,具有实用价值。
关键词 iq DRFM SiMULiNK 信道不平衡性 谐波 交调信号
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