In radio receivers,complete implementation of the software defined radio(SDR) concept is mainly limited by frontend.Based on bandpass sampling(BPS) theory,a flexible digital frontend(DFE) platform for SDR receiver is ...In radio receivers,complete implementation of the software defined radio(SDR) concept is mainly limited by frontend.Based on bandpass sampling(BPS) theory,a flexible digital frontend(DFE) platform for SDR receiver is designed.In order to increase the processing speed,Gigabit Ethernet was applied in the platform at speed of 5×10~8 bit/s.By appropriate design of interpolant according to the position of input RF signals,multi-band receiving can be realized in the platform with suppression more than 35 d B without changing hardware.展开更多
Modern handheld target detection methods are typically restricted to line of sight （LOS） techniques. The design of a new method to detect moving targets through non-transparent surfaces could greatly aid the safety ...Modern handheld target detection methods are typically restricted to line of sight （LOS） techniques. The design of a new method to detect moving targets through non-transparent surfaces could greatly aid the safety of hazardous military and government operations. In this paper, we develop through-wall virtual imaging using Wi-Fi enabled software defined radio to see moving objects and their relative locations. We use LabVIEW and NI Universal Software Radio Peripheral （NI USRP2921 radios with Ettus Research LP0965 directive antennas） devices to detect moving objects behind walls by sending and receiving a signal with respect to the USRP＇s location. Based on the signal-to-interference ratio of our signal （rather than the traditional signal-to-noise method）, we could determine the target object behind the wall. The two major applications for this project are： detecting an active shooter that is standing on the other side of the wall and detecting abnormalities in the human body such as breast cancer with more sensitive antennas. Likewise, firefighters, law enforcement officers, and military men would find more practical purposes for the use of this system in their fields. We evaluate the proposed model using experimental results.展开更多
Software Defined Radio (SDR) architecture allows us to integrate different mobile technologies using common hardware but with different software modules. To achieve this, we need to keep the signal in digital form for...Software Defined Radio (SDR) architecture allows us to integrate different mobile technologies using common hardware but with different software modules. To achieve this, we need to keep the signal in digital form for as much portion of the circuitry as possible, so that the implementation could be carried out by programmable digital processors. For this purpose, the incoming radio frequency (RF) signal is down converted to baseband spectrum using band pass sampling method. Research works carried out so far in this field have developed a few algorithms for band pass sampling. But, these algorithms are not much useful for most of the mobile communication systems and they use complex methodology for computing the sampling frequency values. In order to use the SDR platform to integrate all current wireless technologies, an efficient, cost effective and less complex algorithm that can be labelled as universal band pass sampling algorithm is developed in this paper for multiple mobile systems. This algorithm is based on a novel idea of inserting guard bands between the signals which reduces the design complexities of perfect ADC and sharp cut off filters. Using this algorithm, valid sampling frequency ranges and corresponding IF values are calculated for down converting RF signals. The algorithm is tested for six RF signals of different wireless technologies which are integrated and simultaneously down converted using SDR based front end receiver and thus the system multiplies the base station capacity by a factor of six. The simulation results are obtained and shown in this paper which proves that the algorithm developed works well for most of the wireless technologies.展开更多
Wireless local area network(WLAN) is an indivisible part of the next generation wireless system. In this paper, an open Wi-Fi platform is designed and developed with special consideration of real-time signal processin...Wireless local area network(WLAN) is an indivisible part of the next generation wireless system. In this paper, an open Wi-Fi platform is designed and developed with special consideration of real-time signal processing. Such system can help accelerate research and development of future wireless network, especially in the case of cellular/Wi-Fi co-existing networks. This platform is based on the Intel general-purpose processor and the universal software radio peripheral(USRP) radio front end. The design including the physical layer implementations is purely software and is optimized for real-time signal processing on the general purpose processor. In the lab experiment, this platform supports baseband rate up to 700 Mbps with 2 transmitters in 80 MHz bandwidth. A cellular-Wi-Fi signaling interface between the Wi-Fi access point(AP) and the 5G core network is also developed and validated as an example for wireless resource allocation.展开更多
为有效检测树干分层介质厚度和相对介电常数,该研究提出一种基于雷达探测的树干分层结构介电参数反演方法。基于斯涅耳定律结合树干生理结构特点,构建雷达信号在树干分层结构中的传播模型。利用软件定义无线电平台(software defined rad...为有效检测树干分层介质厚度和相对介电常数,该研究提出一种基于雷达探测的树干分层结构介电参数反演方法。基于斯涅耳定律结合树干生理结构特点,构建雷达信号在树干分层结构中的传播模型。利用软件定义无线电平台(software defined radio,SDR)搭建树干探测雷达。然后采用稀疏分解算法、K-SVD字典训练以及层剥离算法对探测雷达回波信号进行参数反演,并对不同的稀疏分解算法反演结果进行了对比。试验表明在回波混叠和无混叠的情况下,该方法均能够对树干分层介质厚度和相对介电常数进行估算;无混叠时相对介电常数和厚度的反演误差分别在2.93%和3.5%以内,混叠时相对介电常数和厚度的反演误差分别在7.52%和7.61%以内。综合试验结果表明,在5种反演算法中,SAMP算法在未知信号稀疏度的条件下表现最佳,具有较高的反演准确率和鲁棒性。展开更多
This paper reviews the requirements for Software Defi ned Radio (SDR) systems for high-speed wireless applications and compares how well the different technology choices available-from ASICs, FPGAs to digital signal p...This paper reviews the requirements for Software Defi ned Radio (SDR) systems for high-speed wireless applications and compares how well the different technology choices available-from ASICs, FPGAs to digital signal processors (DSPs) and general purpose processors (GPPs) - meet them.展开更多
The fifth generation (5G) New Radio (NR) has been developed to provide significant improvements in scalability, flexibility, and efficiency in terms of power usage and spectrum as well. To meet the 5G vision, service ...The fifth generation (5G) New Radio (NR) has been developed to provide significant improvements in scalability, flexibility, and efficiency in terms of power usage and spectrum as well. To meet the 5G vision, service and performance requirements, various candidate technologies have been proposed in 5G new radio;some are extensions of 4G and, some are developed explicitly for 5G. These candidate technologies include non-Orthogonal Multiple Access (NOMA), and Low Density Parity Check (LDPC) channel coding. In addition, deploying software defined radio (SDR) instead of traditional hardware modules. In this paper we build an open source SDR-based platform to realize the transceiver of the physical downlink shared channel (PDSCH) of 5G NR according to Third Generation Partnership Project (3GPP) standard. We provide a prototype for pairing between two 5G users using NOMA technique. In addition, a suitable design for LDPC channel coding is performed. The intermediate stage of segmentation, rate matching and interleaving are also carried out in order to realize a standard NR frame. Finally, experiments are carried out in both simulation and real time scenario on the designed 5G NR for the purpose of system performance evaluation, and to demonstrate its potential in meeting future 5G mobile network challenges.展开更多
General purpose processer （GPP） based software-defined radio （SDR） platforms provide wireless communication system engineers with maximal architecture flexibility and versatility to construct a wideband wireless c...General purpose processer （GPP） based software-defined radio （SDR） platforms provide wireless communication system engineers with maximal architecture flexibility and versatility to construct a wideband wireless communication system. Nevertheless, the lack of hardware real-time timing control makes it difficult to achieve time synchronization between the base station and the terminals. In this paper, a software-based time synchronization （STS） method is proposed to realize the time synchronization of time division multiple access （TDMA） based wireless communication systems. A high precision software clock source is firstly constructed to measure the elapse of processing time. The Round-Trip Delay （RTD） algorithm is then presented to calculate timing advance values and achieve time synchronization. An example TDMA system is implemented on Microsoft Sora platforms to evaluate is effective to enable time synchronization for wideband the performance. Experiments show that the proposed mechanism wireless communication systems on GPP-based SDR platforms.展开更多
This paper proposes a new low power structure to improve the trade-off between the bandwidth and the power consumption of a programmable gain amplifier（PGA）.The PGA consists of three-stage amplifiers, which includes...This paper proposes a new low power structure to improve the trade-off between the bandwidth and the power consumption of a programmable gain amplifier（PGA）.The PGA consists of three-stage amplifiers, which includes a variable gain amplifier and DC offset cancellation circuits.The cutoff frequency of the DC offset cancellation circuits can be changed from 4 to 80 kHz.The chip was fabricated in 0.13μm CMOS technology. Measurement results showed that the gain of the PGA can be programmed from -5 to 60 dB.At the gain setting of 60 dB,the bandwidth can be tuned from 1 to 10 MHz,while the power consumption can be programmed from 850μA to 3.2 mA at a supply voltage of 1.2 V.Its in-band OIP3 result is at 14 dBm.展开更多
This paper presents a 4th-order reconfigurable analog baseband filter for software-defined radios.The design exploits an active-RC low pass filter（LPF） structure with digital assistant,which is flexible for tunabili...This paper presents a 4th-order reconfigurable analog baseband filter for software-defined radios.The design exploits an active-RC low pass filter（LPF） structure with digital assistant,which is flexible for tunability of filter characteristics,such as cut-off frequency,selectivity,type,noise,gain and power.A novel reconfigurable operational amplifier is proposed to realize the optimization of noise and scalability of power dissipation.The chip was fabricated in an SMIC 0.13μm CMOS process.The main filter and frequency calibration circuit occupy 1.8×0.8 mm;and 0.48×0.25 mm;areas,respectively.The measurement results indicate that the filter provides Butterworth and Chebyshev responses with a wide frequency tuning range from 280 kHz to 15 MHz and a gain range from 0 to 18 dB.An IIP3 of 29 dBm is achieved under a 1.2 V power supply.The input inferred noise density varies from 41 to 133 nV/（Hz）;according to a given standard,and the power consumptions are 5.46 mW for low band（from 280 kHz to 3 MHz） and 8.74 mW for high band（from 3 to 15 MHz） mode.展开更多
基金Project(2013QNA49)supported by the Fundamental Research Funds for the Central Universities,China
文摘In radio receivers,complete implementation of the software defined radio(SDR) concept is mainly limited by frontend.Based on bandpass sampling(BPS) theory,a flexible digital frontend(DFE) platform for SDR receiver is designed.In order to increase the processing speed,Gigabit Ethernet was applied in the platform at speed of 5×10~8 bit/s.By appropriate design of interpolant according to the position of input RF signals,multi-band receiving can be realized in the platform with suppression more than 35 d B without changing hardware.
基金Acknowledgements This work was supported in part by the U.S. National Science Foundation （NSF） under grants CNS-1405670 and CN5-1658972. However, any opinions, findings, and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the NSE
文摘Modern handheld target detection methods are typically restricted to line of sight （LOS） techniques. The design of a new method to detect moving targets through non-transparent surfaces could greatly aid the safety of hazardous military and government operations. In this paper, we develop through-wall virtual imaging using Wi-Fi enabled software defined radio to see moving objects and their relative locations. We use LabVIEW and NI Universal Software Radio Peripheral （NI USRP2921 radios with Ettus Research LP0965 directive antennas） devices to detect moving objects behind walls by sending and receiving a signal with respect to the USRP＇s location. Based on the signal-to-interference ratio of our signal （rather than the traditional signal-to-noise method）, we could determine the target object behind the wall. The two major applications for this project are： detecting an active shooter that is standing on the other side of the wall and detecting abnormalities in the human body such as breast cancer with more sensitive antennas. Likewise, firefighters, law enforcement officers, and military men would find more practical purposes for the use of this system in their fields. We evaluate the proposed model using experimental results.
文摘Software Defined Radio (SDR) architecture allows us to integrate different mobile technologies using common hardware but with different software modules. To achieve this, we need to keep the signal in digital form for as much portion of the circuitry as possible, so that the implementation could be carried out by programmable digital processors. For this purpose, the incoming radio frequency (RF) signal is down converted to baseband spectrum using band pass sampling method. Research works carried out so far in this field have developed a few algorithms for band pass sampling. But, these algorithms are not much useful for most of the mobile communication systems and they use complex methodology for computing the sampling frequency values. In order to use the SDR platform to integrate all current wireless technologies, an efficient, cost effective and less complex algorithm that can be labelled as universal band pass sampling algorithm is developed in this paper for multiple mobile systems. This algorithm is based on a novel idea of inserting guard bands between the signals which reduces the design complexities of perfect ADC and sharp cut off filters. Using this algorithm, valid sampling frequency ranges and corresponding IF values are calculated for down converting RF signals. The algorithm is tested for six RF signals of different wireless technologies which are integrated and simultaneously down converted using SDR based front end receiver and thus the system multiplies the base station capacity by a factor of six. The simulation results are obtained and shown in this paper which proves that the algorithm developed works well for most of the wireless technologies.
基金supported in part by the National Natural Science Foundation of China under Grant No. 61671436the Science and Technology Commission Foundation of Shanghai under Grant No. 15511102602, 16511104204
文摘Wireless local area network(WLAN) is an indivisible part of the next generation wireless system. In this paper, an open Wi-Fi platform is designed and developed with special consideration of real-time signal processing. Such system can help accelerate research and development of future wireless network, especially in the case of cellular/Wi-Fi co-existing networks. This platform is based on the Intel general-purpose processor and the universal software radio peripheral(USRP) radio front end. The design including the physical layer implementations is purely software and is optimized for real-time signal processing on the general purpose processor. In the lab experiment, this platform supports baseband rate up to 700 Mbps with 2 transmitters in 80 MHz bandwidth. A cellular-Wi-Fi signaling interface between the Wi-Fi access point(AP) and the 5G core network is also developed and validated as an example for wireless resource allocation.
文摘为有效检测树干分层介质厚度和相对介电常数,该研究提出一种基于雷达探测的树干分层结构介电参数反演方法。基于斯涅耳定律结合树干生理结构特点,构建雷达信号在树干分层结构中的传播模型。利用软件定义无线电平台(software defined radio,SDR)搭建树干探测雷达。然后采用稀疏分解算法、K-SVD字典训练以及层剥离算法对探测雷达回波信号进行参数反演,并对不同的稀疏分解算法反演结果进行了对比。试验表明在回波混叠和无混叠的情况下,该方法均能够对树干分层介质厚度和相对介电常数进行估算;无混叠时相对介电常数和厚度的反演误差分别在2.93%和3.5%以内,混叠时相对介电常数和厚度的反演误差分别在7.52%和7.61%以内。综合试验结果表明,在5种反演算法中,SAMP算法在未知信号稀疏度的条件下表现最佳,具有较高的反演准确率和鲁棒性。
文摘This paper reviews the requirements for Software Defi ned Radio (SDR) systems for high-speed wireless applications and compares how well the different technology choices available-from ASICs, FPGAs to digital signal processors (DSPs) and general purpose processors (GPPs) - meet them.
文摘The fifth generation (5G) New Radio (NR) has been developed to provide significant improvements in scalability, flexibility, and efficiency in terms of power usage and spectrum as well. To meet the 5G vision, service and performance requirements, various candidate technologies have been proposed in 5G new radio;some are extensions of 4G and, some are developed explicitly for 5G. These candidate technologies include non-Orthogonal Multiple Access (NOMA), and Low Density Parity Check (LDPC) channel coding. In addition, deploying software defined radio (SDR) instead of traditional hardware modules. In this paper we build an open source SDR-based platform to realize the transceiver of the physical downlink shared channel (PDSCH) of 5G NR according to Third Generation Partnership Project (3GPP) standard. We provide a prototype for pairing between two 5G users using NOMA technique. In addition, a suitable design for LDPC channel coding is performed. The intermediate stage of segmentation, rate matching and interleaving are also carried out in order to realize a standard NR frame. Finally, experiments are carried out in both simulation and real time scenario on the designed 5G NR for the purpose of system performance evaluation, and to demonstrate its potential in meeting future 5G mobile network challenges.
基金Supported by the Major Project of Beijing Municipal Natural Science Foundation of China under Grant No. 4110001
文摘General purpose processer （GPP） based software-defined radio （SDR） platforms provide wireless communication system engineers with maximal architecture flexibility and versatility to construct a wideband wireless communication system. Nevertheless, the lack of hardware real-time timing control makes it difficult to achieve time synchronization between the base station and the terminals. In this paper, a software-based time synchronization （STS） method is proposed to realize the time synchronization of time division multiple access （TDMA） based wireless communication systems. A high precision software clock source is firstly constructed to measure the elapse of processing time. The Round-Trip Delay （RTD） algorithm is then presented to calculate timing advance values and achieve time synchronization. An example TDMA system is implemented on Microsoft Sora platforms to evaluate is effective to enable time synchronization for wideband the performance. Experiments show that the proposed mechanism wireless communication systems on GPP-based SDR platforms.
基金Project supported by the National High-Tech Research and Development Program of China(No.2009AA011606)the National Natural Science Foundation of China(No.60976023)
文摘This paper proposes a new low power structure to improve the trade-off between the bandwidth and the power consumption of a programmable gain amplifier（PGA）.The PGA consists of three-stage amplifiers, which includes a variable gain amplifier and DC offset cancellation circuits.The cutoff frequency of the DC offset cancellation circuits can be changed from 4 to 80 kHz.The chip was fabricated in 0.13μm CMOS technology. Measurement results showed that the gain of the PGA can be programmed from -5 to 60 dB.At the gain setting of 60 dB,the bandwidth can be tuned from 1 to 10 MHz,while the power consumption can be programmed from 850μA to 3.2 mA at a supply voltage of 1.2 V.Its in-band OIP3 result is at 14 dBm.
基金Project supported by the Important National Science and Technology Specific Projects of China(No2009ZX01031-003-002)the National High Technology Research and Development Program of China(No2009AA011605)the National Natural Science Foundation of China(No61076028)
文摘This paper presents a 4th-order reconfigurable analog baseband filter for software-defined radios.The design exploits an active-RC low pass filter（LPF） structure with digital assistant,which is flexible for tunability of filter characteristics,such as cut-off frequency,selectivity,type,noise,gain and power.A novel reconfigurable operational amplifier is proposed to realize the optimization of noise and scalability of power dissipation.The chip was fabricated in an SMIC 0.13μm CMOS process.The main filter and frequency calibration circuit occupy 1.8×0.8 mm;and 0.48×0.25 mm;areas,respectively.The measurement results indicate that the filter provides Butterworth and Chebyshev responses with a wide frequency tuning range from 280 kHz to 15 MHz and a gain range from 0 to 18 dB.An IIP3 of 29 dBm is achieved under a 1.2 V power supply.The input inferred noise density varies from 41 to 133 nV/（Hz）;according to a given standard,and the power consumptions are 5.46 mW for low band（from 280 kHz to 3 MHz） and 8.74 mW for high band（from 3 to 15 MHz） mode.
