超宽带微波接收前端是超宽带微波阵列接收机的核心电路,决定了接收机的噪声、动态、抗干扰等多项关键指标,而小型化、集成化设计更是微波超宽带前端研究的主要方向。文中通过对微波超宽带前端使用要求及技术方案的分析,结合专用多功能...超宽带微波接收前端是超宽带微波阵列接收机的核心电路,决定了接收机的噪声、动态、抗干扰等多项关键指标,而小型化、集成化设计更是微波超宽带前端研究的主要方向。文中通过对微波超宽带前端使用要求及技术方案的分析,结合专用多功能芯片设计及系统集成设计,实现了一个新型的小型化双通道微波超宽带接收前端模块。整个模块尺寸仅为50 mm×36 mm×15 mm,工作频率2~18 GHz,采用8段集成开关预选滤波器芯片实现全频段覆盖,典型增益26~30 d B,噪声系数<6.5 d B。展开更多
Ultra-wide-band (UWB) signals are suitable for localization, since their high time resolution can provide precise time of arrival (TOA) estimation. However, one major challenge in UWB signal processing is the requirem...Ultra-wide-band (UWB) signals are suitable for localization, since their high time resolution can provide precise time of arrival (TOA) estimation. However, one major challenge in UWB signal processing is the requirement of high sampling rate which leads to complicated signal processing and expensive hardware. In this paper, we present a novel UWB signal sampling method called UWB signal sampling via temporal sparsity (USSTS). Its sampling rate is much lower than Nyquist rate. Moreover, it is implemented in one step and no extra processing unit is needed. Simulation results show that USSTS can not recover the signal precisely, but for the use in localization, the accuracy of TOA estimation is the same as that in traditional methods. Therefore, USSTS gives a novel and effective solution for the use of UWB signals in localization.展开更多
An ultra-wideband 4 GS/s 4 bit analog-to-digital converter（ADC）which is fabricated in 2-level interconnect, 1.4μm InGaP/GaAs HBT technology is presented.The ADC has a-3 dB analog bandwidth of 3.8 GHz and an effecti...An ultra-wideband 4 GS/s 4 bit analog-to-digital converter（ADC）which is fabricated in 2-level interconnect, 1.4μm InGaP/GaAs HBT technology is presented.The ADC has a-3 dB analog bandwidth of 3.8 GHz and an effective resolution bandwidth（ERBW）of 2.6 GHz.The ADC adopts folding-interpolating architecture to minimize its size and complexity.A novel bit synchronization circuit is used in the coarse quantizer to eliminate the glitch codes of the ADC.The measurement results show that the chip achieves larger than 3.4 ENOBs with an input frequency band of DC-2.6 GHz and larger than 3.0 ENOBs within DC-4GHz at 4 GS/s.It has 3.49 ENOBs when increasing input power by 4 dB at 6.001 GHz of input.That indicates that the ADC has the ability of sampling signals from 1st to 3rd Nyquist zones（DC-6 GHz）.The measured DNL and INL are both less than±0.15 LSB. The ADC consumes power of 1.98 W and occupies a total area of 1.45×1.45 mm^2.展开更多
The analytic representation of the transient radiation for an aperture excited by a rectangle pulse is obtained. It shows that the field duration and amplitude depend on the observation distance, the elevation angle, ...The analytic representation of the transient radiation for an aperture excited by a rectangle pulse is obtained. It shows that the field duration and amplitude depend on the observation distance, the elevation angle, the pulse width of the rectangle pulse and the aperture size.展开更多
The picosecond photoconductive switches are developed and used to detect the pulse laser waveform. By using the photoconductive switches, an novel lab model of ultra-wide band(UWB) radar is also developed. The experim...The picosecond photoconductive switches are developed and used to detect the pulse laser waveform. By using the photoconductive switches, an novel lab model of ultra-wide band(UWB) radar is also developed. The experimental results are given to show the performances of the switches and the UWB radar.展开更多
Ultra-wide-band (UWB) technology combined with multiple input and multiple output (MIMO) provides a viable solution for achieving high data transmission rates of more than 1 Gb/s in wireless communications. UWB is typ...Ultra-wide-band (UWB) technology combined with multiple input and multiple output (MIMO) provides a viable solution for achieving high data transmission rates of more than 1 Gb/s in wireless communications. UWB is typically applied to short-range indoor environments and is therefore characterized by dense multipath propagation. In this type of environment, MIMO systems allow for a substantial improvement in the spectral efficiency by exploiting the inherent array gain and spatial multiplexing gain of UWB systems. This paper investigates the channel capacity of UWB-MIMO wireless technology and shows that UWB and MIMO designs improve the spectral efficiency logarithmically and linearly, respectively.展开更多
文摘超宽带微波接收前端是超宽带微波阵列接收机的核心电路,决定了接收机的噪声、动态、抗干扰等多项关键指标,而小型化、集成化设计更是微波超宽带前端研究的主要方向。文中通过对微波超宽带前端使用要求及技术方案的分析,结合专用多功能芯片设计及系统集成设计,实现了一个新型的小型化双通道微波超宽带接收前端模块。整个模块尺寸仅为50 mm×36 mm×15 mm,工作频率2~18 GHz,采用8段集成开关预选滤波器芯片实现全频段覆盖,典型增益26~30 d B,噪声系数<6.5 d B。
基金supported by National science foundation(No. 60772035): Key technique study on heterogeneous network convergenceDoctoral grant(No.20070004010)s: Study on cross layer design for heterogeneous network convergence+1 种基金National 863 Hi-Tech Projects(No.2007AA01Z277): Pa-rameter design based electromagnetic compatibility study in cognitive radio communication systemNational science foundation(No. 60830001): Wireless communication fundamentals and key techniuqes for high speed rail way control and safety data transmission
文摘Ultra-wide-band (UWB) signals are suitable for localization, since their high time resolution can provide precise time of arrival (TOA) estimation. However, one major challenge in UWB signal processing is the requirement of high sampling rate which leads to complicated signal processing and expensive hardware. In this paper, we present a novel UWB signal sampling method called UWB signal sampling via temporal sparsity (USSTS). Its sampling rate is much lower than Nyquist rate. Moreover, it is implemented in one step and no extra processing unit is needed. Simulation results show that USSTS can not recover the signal precisely, but for the use in localization, the accuracy of TOA estimation is the same as that in traditional methods. Therefore, USSTS gives a novel and effective solution for the use of UWB signals in localization.
基金Project supported by the State Key Development Program for Basic Research of China(No2010CB327505)
文摘An ultra-wideband 4 GS/s 4 bit analog-to-digital converter（ADC）which is fabricated in 2-level interconnect, 1.4μm InGaP/GaAs HBT technology is presented.The ADC has a-3 dB analog bandwidth of 3.8 GHz and an effective resolution bandwidth（ERBW）of 2.6 GHz.The ADC adopts folding-interpolating architecture to minimize its size and complexity.A novel bit synchronization circuit is used in the coarse quantizer to eliminate the glitch codes of the ADC.The measurement results show that the chip achieves larger than 3.4 ENOBs with an input frequency band of DC-2.6 GHz and larger than 3.0 ENOBs within DC-4GHz at 4 GS/s.It has 3.49 ENOBs when increasing input power by 4 dB at 6.001 GHz of input.That indicates that the ADC has the ability of sampling signals from 1st to 3rd Nyquist zones（DC-6 GHz）.The measured DNL and INL are both less than±0.15 LSB. The ADC consumes power of 1.98 W and occupies a total area of 1.45×1.45 mm^2.
文摘The analytic representation of the transient radiation for an aperture excited by a rectangle pulse is obtained. It shows that the field duration and amplitude depend on the observation distance, the elevation angle, the pulse width of the rectangle pulse and the aperture size.
文摘The picosecond photoconductive switches are developed and used to detect the pulse laser waveform. By using the photoconductive switches, an novel lab model of ultra-wide band(UWB) radar is also developed. The experimental results are given to show the performances of the switches and the UWB radar.
文摘Ultra-wide-band (UWB) technology combined with multiple input and multiple output (MIMO) provides a viable solution for achieving high data transmission rates of more than 1 Gb/s in wireless communications. UWB is typically applied to short-range indoor environments and is therefore characterized by dense multipath propagation. In this type of environment, MIMO systems allow for a substantial improvement in the spectral efficiency by exploiting the inherent array gain and spatial multiplexing gain of UWB systems. This paper investigates the channel capacity of UWB-MIMO wireless technology and shows that UWB and MIMO designs improve the spectral efficiency logarithmically and linearly, respectively.
