- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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The impact of out of band emissions: A measurement based performance comparison of UF-OFDM and CP-OFDM
摘要： Long Term Evolution (LTE) networks, along with their recent releases, rely on the cyclic prefix orthogonal frequency division multiplexing (CP-OFDM) waveform as the foundation. However, high sidelobes, synchronization problems and spectral efficiency constraints of CP-OFDM cannot meet future requirements of cellular network design targets. At this point, universal filtered orthogonal frequency division multiplexing (UF-OFDM) emerges as a strong candidate. Equipped with the advantages of using filters, UF-OFDM provides additional design flexibility to address the fundamental problems of CP-OFDM. In this study, the effect of adjacent channels that causes interference between different frequency channels because of out-of-band (OoB) emissions on UF-OFDM performance is investigated by performing real-time tests on software defined radio (SDR) nodes with multiple reception paths. Frequency domain carrier frequency offset (CFO) and symbol timing offset (STO) correction techniques are used. By the application of the same correction approaches to CP-OFDM, these two waveforms are evaluated in terms of signal to noise ratio (SNR), bit/symbol error rate (BER/SER) and error vector magnitude (EVM). Test results indicate that, based on lower OoB emissions, UF-OFDM uses the spectrum more efficiently and provides better results than CP-OFDM in congested environments.
关键词： synchronization,CP-OFDM,out-of-band emissions,software defined radio nodes,UF-OFDM
更新于2025-09-23 15:23:52
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[IEEE 2018 New Trends in Signal Processing (NTSP) - Liptovsky Mikulá?, Slovakia (2018.10.10-2018.10.12)] 2018 New Trends in Signal Processing (NTSP) - Possibilities of Using FSO/RF Technology in Military Communication Systems
摘要： The article presents an overview of selected aspects of wireless communications considering military applications. The main attention is paid to performance analysis of radio and free space optics technologies. There are also presented some activities to get new capabilities of wireless communications using procedure of dynamic spectrum access, wideband and narrowband radio system, and free space optical system operated in infrared spectrum. In the summary, possibilities of radio-optical hybrid communication systems and their application in military areas have been defined.
关键词： hybrid wireless communications,frequency management,software-defined radio,frequency broker,cognitive radio
更新于2025-09-23 15:22:29
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[IEEE 2018 IEEE International Conference on RFID Technology & Application (RFID-TA) - Macau, Macao (2018.9.26-2018.9.28)] 2018 IEEE International Conference on RFID Technology & Application (RFID-TA) - Perfectly Synchronized Streaming from Digitally Modulated Multiple Backscatter Sensor Tags
摘要： This paper proposes a multiple access method, referred to as Multiple Subcarrier Multiple Access (MSMA), for perfectly synchronized concurrent data collection from a group of passive backscatter wireless sensor tags and its experimental evaluation. By achieving less than 128 micro second synchronization error, backscatter communications can be applied to structural health monitoring of artifacts such as civil structures and machineries. In MSMA, each sensor tag uses a dedicated subcarrier frequency to produce a modulated backscatter. The sensor data is superposed onto the subcarrier either with an analog or a digital modulation. The inevitable harmonics among the subcarriers, stemming from the backscatter principle, can be rejected by numerically calculating the harmonic replicas and subtracting them from the observed signal in a software defined receiver. A frame based signal processing in the receiver results in no relative synchronization error among subcarriers even after the interference rejection. Since the interference rejection can be done before the demodulation and decoding, the concurrency can be secured irrespective to the choice of modulation method. We developed a prototype of MSMA using LabVIEW communications Software Defined Radio environment and prototype sensor tags using discrete electrical parts. The performances and limitation of MSMA using digitally modulated subcarriers are evaluated both in wired and wireless environments with up to four backscatter sensors.
关键词： Structural Health Monitoring,Software Defined Radio,Interference Rejection,Passive backscatter
更新于2025-09-23 15:22:29
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[IEEE 2019 6th International Conference on Electric Vehicular Technology (ICEVT) - Bali, Indonesia (2019.11.18-2019.11.21)] 2019 6th International Conference on Electric Vehicular Technology (ICEVT) - Experimental Method for Improving Efficiency on Photovoltaic Cell Using Passive Cooling and Floating Method
摘要： Software-defined radio (SDR) allows the unprecedented levels of flexibility by transitioning the radio communication system from a rigid hardware platform to a more user-controlled software paradigm. However, it can still be time-consuming to design and implement such SDRs as they typically require thorough knowledge of the operating environment and a careful tuning of the program. In this paper, our contribution is the design of a bidirectional transceiver that runs on the commonly used USRP platform and implemented in MATLAB using standard tools like MATLAB Coder and MEX to speed up the processing steps. We outline strategies on how to create a state-action-based design, wherein the same node switches between transmitter and receiver functions. Our design allows the optimal selection of the parameters toward meeting the timing requirements set forth by various processing blocks associated with a differential binary phase shift keying physical layer and CSMA/CA/ACK MAC layer, so that all the operations remain functionally compliant with the IEEE 802.11b standard for the 1 Mb/s specification. The code base of the system is enabled through the Communications System Toolbox and incorporates channel sensing and exponential random back-off for contention resolution. The current work provides an experimental testbed that enables the creation of new MAC protocols starting from the fundamental IEEE 802.11b standard. Our design approach guarantees consistent performance of the bi-directional link, and the three-node experimental results demonstrate the robustness of the system in mitigating packet collisions and enforcing fairness among nodes, making it a feasible framework in higher layer protocol design.
关键词： Software defined radio,IEEE 802.11b,exponential random back-off,MEX,CSMA/CA/ACK,reconfigurable computing,energy detection
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Sozopol, Bulgaria (2019.9.6-2019.9.8)] 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers (CAOL) - Photomedicine and Its Place in Medicine of the 21th Century
摘要： Digital television signal is a promising signal of opportunity for wireless positioning. This paper studies the time of arrival (TOA) estimation on the European standard DVB-T signals in the context of positioning. Theoretical analysis on the autocorrelation of the pilot signal and multipath error envelop suggests that DVB-T has the appropriate characteristics for positioning. A software defined radio-based DVB-T receiver is developed for field testing, in which the radio frequency DVB-T signals are first sampled by universal software radio peripheral, and then algorithms of the coarse symbol synchronization, the pilot detection, the first path acquisition, and the delay tracking are sequentially performed to obtain the TOA estimation. To quantify the TOA tracking results on real DVB-T signals, field testing campaigns are carried out in five cities in Southern France. Test results showed that, in the high signal-noise ratio condition, the 2-σ error interval is within 1 m. By taking into account all the field tests, the interval of 95% accuracy is within 4 m and the corresponding C/N0 varies from 48 to 62 dB-Hz. In addition, with the developed TOA estimation method, the synchronization of the emitters with global positioning system time is evaluated and the distance difference of the multiple emitters within single frequency networks are also measured during the tests.
关键词： delay locked loop,software defined radio (SDR),wireless positioning,Digital TV,orthogonal frequency division multiplexing (OFDM),time of arrival
更新于2025-09-23 15:19:57
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[IEEE 2019 URSI Asia-Pacific Radio Science Conference (AP-RASC) - New Delhi, India (2019.3.9-2019.3.15)] 2019 URSI Asia-Pacific Radio Science Conference (AP-RASC) - Design of a Synchronous Counter with Two-dimensional 10 x 10 LED array for Calibration of Timing Parameters of Video Cameras
摘要： Digital television signal is a promising signal of opportunity for wireless positioning. This paper studies the time of arrival (TOA) estimation on the European standard DVB-T signals in the context of positioning. Theoretical analysis on the autocorrelation of the pilot signal and multipath error envelop suggests that DVB-T has the appropriate characteristics for positioning. A software defined radio-based DVB-T receiver is developed for field testing, in which the radio frequency DVB-T signals are first sampled by universal software radio peripheral, and then algorithms of the coarse symbol synchronization, the pilot detection, the first path acquisition, and the delay tracking are sequentially performed to obtain the TOA estimation. To quantify the TOA tracking results on real DVB-T signals, field testing campaigns are carried out in five cities in Southern France. Test results showed that, in the high signal-noise ratio condition, the 2-σ error interval is within 1 m. By taking into account all the field tests, the interval of 95% accuracy is within 4 m and the corresponding C/N0 varies from 48 to 62 dB-Hz. In addition, with the developed TOA estimation method, the synchronization of the emitters with global positioning system time is evaluated and the distance difference of the multiple emitters within single frequency networks are also measured during the tests.
关键词： delay locked loop,software defined radio (SDR),wireless positioning,Digital TV,orthogonal frequency division multiplexing (OFDM),time of arrival
更新于2025-09-16 10:30:52
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Four-PAM Modulation of Ambient FM Backscattering for Spectrally Efficient Low-Power Applications
摘要： Ambient backscatter uses radio frequency signals available in the environment (e.g., radio broadcasting, television, or mobile telephony) to transmit data effectively leading to significant energy and cost efficiency increase. This paper presents a novel wireless tag, which for the first time utilizes 4-pulse amplitude modulation technique to modulate the ambient backscattered FM signals in order to send data to a nearby low-cost software defined radio reader. The tag is based on an RF front-end that uses a single transistor controlled by an ultralow-power microcontroller. The microcontroller includes an analog-to-digital converter for sensing and a digital-to-analog converter for RF front-end control. A proof-of-concept prototype is demonstrated in an indoor environment with the low bit rate of 345 b/s and power consumption 27 μW. It operated using a real FM station at 34.5 km away and the tag-to-reader distance was tested at 1 m. The value of energy spent in this modulator was 78.2 nJ/bit at 345 b/s and 27.7 nJ/bit at 10.2 kb/s.
关键词： Internet-of-Things (IoT),backscatter communication,Ambient backscattering,software-defined radio (SDR),pulse amplitude modulation (PAM),FM modulation,radio frequency identification (RFID) sensors
更新于2025-09-10 09:29:36
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Latency analysis on W-band hybrid fiber-wireless link using software defined radio in real time
摘要： This paper reports an experimental comparison and analysis of latency for different modulation techniques at different data rates in W-band Radio-over-Fiber (RoF) transmission links. In addition, a software defined radio called GNU-Radio is employed with Universal Software Radio Peripherals (USRP) to generate and retrieve the transmitted signals. Likewise, it is used to test the end to end latency in the W-band RoF link. Our main contribution is achieving a W-Band low-latency wireless fiber link which fits to the key performance indicators of 5G networks.
关键词： Radio over Fiber,W band,Network Performance,Software defined radio
更新于2025-09-04 15:30:14
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Smart Receivers with Modular and Multifunctional Front-End Blocks: The Benefits of Using Programmable Modulators and Demodulators
摘要： This article presents a technique to convert a standard TV receiver into an intelligent communication hub for smart home applications. The transformation of a standard TV receiver is achieved by introducing a modular front-end block, designed with a programmable modulator and demodulator based on the software-defined radio (SDR) concept. Programmable modulators and demodulators can receive different types of signals and transform one type of signal to another. A multifunctional front-end block will transform a standard TV receiver into a smart receiver.
关键词： modular front-end,software-defined radio,smart receivers,programmable modulators,smart home,demodulators
更新于2025-09-04 15:30:14