摘要 :
Ultra wideband (UWB) radio positioning systems are being developed for many emerging applications. This paper is aimed at addressing the aspect of the antenna by identifying the main requirements and technical challenges, and exam...
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Ultra wideband (UWB) radio positioning systems are being developed for many emerging applications. This paper is aimed at addressing the aspect of the antenna by identifying the main requirements and technical challenges, and examining available antennas so as to find suitable solutions for this special application.
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摘要 :
A new 3D spherical ultra wideband antenna is presented in this paper. Achieving an acceptable return loss, the antenna geometry is modified to highly reduce the weight of the antenna.
摘要 :
Three dimensional (3D) radiation pattern of an antenna mounted at a drone can significantly influence the air-to-ground (A2G) link quality. Even when a drone transmitter is very close to a ground receiver, if the antenna orientati...
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Three dimensional (3D) radiation pattern of an antenna mounted at a drone can significantly influence the air-to-ground (A2G) link quality. Even when a drone transmitter is very close to a ground receiver, if the antenna orientations are not aligned properly, a significant degradation can be observed in the received signal power at the receiver. To characterize such effects for a doughnut-shaped antenna radiation pattern, using an ultra-wideband (UWB) transmitter at the drone and a UWB receiver at the ground, we carry out A2G channel measurements to capture the link quality at the ground receiver for various link distances, drone heights, and antenna orientations. We develop a simple analytical model to approximate the influence of 3D antenna patterns on the received signal strength (RSS), which show reasonable agreement with measurements despite the simplicity of the model and the complicated 3D radiation from the UWB antennas. We also explore how the signal strength can be improved when multiple antennas with different orientations are utilized at transmitter/receiver.
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摘要 :
Three dimensional (3D) radiation pattern of an antenna mounted at a drone can significantly influence the air-to-ground (A2G) link quality. Even when a drone transmitter is very close to a ground receiver, if the antenna orientati...
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Three dimensional (3D) radiation pattern of an antenna mounted at a drone can significantly influence the air-to-ground (A2G) link quality. Even when a drone transmitter is very close to a ground receiver, if the antenna orientations are not aligned properly, a significant degradation can be observed in the received signal power at the receiver. To characterize such effects for a doughnut-shaped antenna radiation pattern, using an ultra-wideband (UWB) transmitter at the drone and a UWB receiver at the ground, we carry out A2G channel measurements to capture the link quality at the ground receiver for various link distances, drone heights, and antenna orientations. We develop a simple analytical model to approximate the influence of 3D antenna patterns on the received signal strength (RSS), which show reasonable agreement with measurements despite the simplicity of the model and the complicated 3D radiation from the UWB antennas. We also explore how the signal strength can be improved when multiple antennas with different orientations are utilized at transmitter/receiver.
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摘要 :
Signal acquisition is a critical step for the ultrawideband (UWB) communication link to be set up, thus, accurate acquisition performance analysis is of practical importance. In this paper, we analyze the pulse-level acquisition p...
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Signal acquisition is a critical step for the ultrawideband (UWB) communication link to be set up, thus, accurate acquisition performance analysis is of practical importance. In this paper, we analyze the pulse-level acquisition performance of differential coherent and noncoherent acquisition schemes combined with a novel hopping method, nonconsecutive search (NCS) and path diversity (PD) for fast and low-complexity UWB acquisition over multipath channels. We derive the receiver output statistics and acquisition probabilities valid for arbitrary order of path diversity and for both differential and noncoherent acquisitions. Furthermore, using a generating function (GF)-based method, we accurately evaluate the mean, variance and the distribution function of the acquisition time TA, accounting for the effect of multiple co-channel interferers and multipath fading channels. Simulation and numerical results verify our analysis and show the large performance enhancement realized by NCS/PD than the serial search.
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摘要 :
Signal acquisition is a critical step for the ultrawideband (UWB) communication link to be set up, thus, accurate acquisition performance analysis is of practical importance. In this paper, we analyze the pulse-level acquisition p...
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Signal acquisition is a critical step for the ultrawideband (UWB) communication link to be set up, thus, accurate acquisition performance analysis is of practical importance. In this paper, we analyze the pulse-level acquisition performance of differential coherent and noncoherent acquisition schemes combined with a novel hopping method, nonconsecutive search (NCS) and path diversity (PD) for fast and low-complexity UWB acquisition over multipath channels. We derive the receiver output statistics and acquisition probabilities valid for arbitrary order of path diversity and for both differential and noncoherent acquisitions. Furthermore, using a generating function (GF)-based method, we accurately evaluate the mean, variance and the distribution function of the acquisition time TA, accounting for the effect of multiple co-channel interferers and multipath fading channels. Simulation and numerical results verify our analysis and show the large performance enhancement realized by NCS/PD than the serial search.
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摘要 :
Life detection using ultra-wideband impulse radar is susceptible to various kinds of interference, including dominant background clutter, radio frequency interference (RFI), disturbance caused by the radar hardware, thermal noise,...
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Life detection using ultra-wideband impulse radar is susceptible to various kinds of interference, including dominant background clutter, radio frequency interference (RFI), disturbance caused by the radar hardware, thermal noise, etc. An interference suppression algorithm based on eigendecomposition is proposed. In the fast-time domain, the proposed algorithm has the ability to remove the interferences in the radar operating band. In the slow-time domain, the proposed algorithm can suppress the interferences in the respiratory signal frequency band, 0.17 to 2HZ. Experimental results demonstrate that the proposed algorithm further improves SNR without respiratory signal suppression.
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摘要 :
Life detection using ultra-wideband impulse radar is susceptible to various kinds of interference, including dominant background clutter, radio frequency interference (RFI), disturbance caused by the radar hardware, thermal noise,...
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Life detection using ultra-wideband impulse radar is susceptible to various kinds of interference, including dominant background clutter, radio frequency interference (RFI), disturbance caused by the radar hardware, thermal noise, etc. An interference suppression algorithm based on eigendecomposition is proposed. In the fast-time domain, the proposed algorithm has the ability to remove the interferences in the radar operating band. In the slow-time domain, the proposed algorithm can suppress the interferences in the respiratory signal frequency band, 0.17 to 2HZ. Experimental results demonstrate that the proposed algorithm further improves SNR without respiratory signal suppression.
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In this paper, we present a method allowing the modeling of UWB antennas as systems described by state representation. The suggested technique should prove to be useful for system- level simulations of UWB communications, in order...
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In this paper, we present a method allowing the modeling of UWB antennas as systems described by state representation. The suggested technique should prove to be useful for system- level simulations of UWB communications, in order to improve the performance of the transceivers taking into account the effects of antennas and thanks to recent techniques of automatic control.
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摘要 :
This paper communicates a design of ultra-wideband planar antenna with a defective ground and the performance characteristics are analysed in this study. The proposed antenna with the dimension of 0.42λg ×0.42 λ g has 4.21 dBi ...
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This paper communicates a design of ultra-wideband planar antenna with a defective ground and the performance characteristics are analysed in this study. The proposed antenna with the dimension of 0.42λg ×0.42 λ g has 4.21 dBi peak gain, omnidirectional radiation pattern and above 80% efficiency over the full UWB working spectrum. The antenna is designed using Rogers RO3003 substrate and provides a large frequency coverage of 3.1 GHz and 13.4 GHz (S11 < −10 dB) with impedance bandwidth of 10.3 GHz. The simulation results for the developed UWB planar antenna demonstrate that it works well and is appropriate for high-speed communication.
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